Easy to make
Topping that stays on top
The custom of sipping a hot beverage while enjoying a sweet cake or bread goes back to 17th-century Europe when German, Dutch, and Scandinavian cooks were habitual pastry makers and coffee was fast becoming part of the daily routine. Eventually, the practice spread to the United States, and today, three types of coffee cake are common: the yeasted kind, featuring a sweet cheese and/or fruit filling; the rich sour cream Bundt version that shows off elegant bands of crumb filling when sliced; and the streusel-topped type, with a nutty crunch highlighting a moist cake. It is this last cake that appeals to me the most. Instead of drawing attention with graceful swirls of filling or the dramatic curves of a Bundt shape, its focus is on the contrasting textures and complementary flavors of the cake and topping.
The trouble is, many such coffee cake recipes are relatively complicated, requiring multiple bowls and appliances. I wanted a simpler method suitable for off-the-cuff baking—but one that produced the same tender cake and crunchy, flavorful topping.
Working in Stages
The cake portion of this treat is commonly made by creaming butter and sugar using a handheld or stand mixer and then alternately incorporating the flour and liquid ingredients. Since I like to use a food processor to chop nuts for streusel and I wanted to avoid dirtying a second appliance, my first instinct was to adapt this method to a food processor. But while the food processor deftly whipped the butter and sugar into a pale, aerated state, its powerful motor was incapable of gently folding in flour and liquids. The result of those aggressively whizzing blades was one seriously tough cake. That's because flour contains proteins, which, in the presence of water, link up to form gluten. As the gluten strands are manipulated by mixing, they link and form a stretchy network. While some gluten is necessary to give baked goods structure, cakes with too much gluten are unpleasantly tough.
Luckily, there was another method to consider. Reverse creaming—what pastry texts refer to as a “two-stage” method—limits gluten formation by “waterproofing” the gluten-forming proteins. Without access to water, gluten can't develop, so the method virtually guarantees a soft, tender crumb. It goes like this: In stage one, you work the butter into the dry ingredients until the flour is mostly coated in fat. In stage two, you mix in the wet ingredients. It seemed like the technique would adapt well to a food processor, so it was definitely worth trying.
From the Top
Since I planned to use the food processor for both components of my coffee cake, I started by making the streusel. I prepared a standard topping by processing toasted pecans (their slightly sweet, buttery flavor makes them a favorite for streusel) and brown sugar until the nuts were finely ground. Then it was a simple matter of incorporating flour, cinnamon, salt, and finally, some melted butter.
After scraping the streusel from the processor bowl and setting it aside, I prepared the cake batter using a recipe I'd cobbled together from my research. First, I whizzed together flour, sugar, baking soda, baking powder, salt, and cinnamon. Then I added softened butter and pulsed until only very small pieces of the butter remained. Finally, I pulsed in milk, an egg, an egg yolk (for extra richness), and vanilla extract to form a thick batter. After scraping the batter into a greased and floured round cake pan, I smoothed the top with a rubber spatula, sprinkled the streusel evenly over the top, and baked the cake in a 350-degree oven.
An hour later, as I was flipping the cake out of the pan and inverting it onto a wire rack to cool, I could see that my streusel—though it was wonderfully nutty and delicately spiced—needed some help. It was sinking into the batter at the edge, losing its crunch and marring the cake's appearance. What's more, it was too fine and rained down from the pan when I inverted the cake. The good news was that the reverse-creaming method had lived up to my expectations: The cake itself was tender as could be.
But back to the streusel. It didn't make sense to invert a cake with a crumbly topping. How about switching from the typical cake pan to a springform pan, which would allow me to remove the collar without dislodging the topping?
I gave it a go. Once the springform pan was prepared, I set it on a rimmed baking sheet to catch any batter that oozed out. To help the streusel cling together, I added 1 teaspoon of water. After just a couple of pulses, I could see that this seemingly minor addition made this batch much more cohesive. After scattering the topping over the batter, I placed my assembled cake in the oven. When I released the collar on the springform pan and sliced the cooled cake, I was pleased to see that this streusel was just right, boasting a cohesive, lightly clumped texture.
Now I just needed to prevent the streusel from disappearing into the edges of the cake. To better understand the problem, I peered into the oven to monitor a batter-filled pan during baking. After a while, I realized that the streusel wasn't actually sinking at all. Rather, the cake batter at the edges, nearest the hot pan, was heating up first and thus thinning out, filling with bubbles from the leavener, and climbing the sides of the pan, where it flowed over onto the streusel.
At first I thought I needed to reduce the amount of leavener in the cake to prevent it from rising so much, but no matter how much I cut back and no matter what combination of baking soda and baking powder I tried, I couldn't stop the cake from rising up and over onto sections of the streusel. Furthermore, in some cases, the reduction in leavening produced a dense, heavy crumb.
Stabilizing the Streusel
During testing, we noticed that the streusel at the edges of the cake sometimes appeared to sink into the batter. Eventually, we realized that it was actually the cake batter and not the streusel that was on the move. As the batter at the edges of the pan heats up, it becomes more fluid and rises, eventually flowing over the topping. To solve the problem, we added extra flour to stiffen the batter and prevent it from climbing up and over the streusel.
What ultimately worked was increasing the viscosity of the batter to make it less prone to climbing. I had been using 1½ cups of flour and decided to bump the amount up to 1⅔ cups. Sure enough, this slight addition thickened and firmed the batter just enough to keep it and the streusel in place at the edges as it heated up. And fortunately, the additional flour wasn't enough to make the crumb noticeably drier.
Each bite of this coffee cake offered an appealing combination of crunchy cinnamon-pecan streusel and rich, tender cake. And I could make it quickly, using a single kitchen appliance.
A Better Way to Make Coffee Cake
We rewrote the rule book on coffee cake, changing up both the equipment and the mixing method.
Keys to Success
Easy to makeA food processor makes chopping the pecans, mixing the streusel, and whipping up the batter quick and easy—and dirties only a single appliance.
Tender crumbFor a tender crumb, we combine the butter and flour before adding the wet ingredients. This coats the flour’s proteins in fat and prevents them from forming gluten.
Cohesive streuselA small amount of water added to the streusel brings it together in clumps that crisp in the oven and adhere better to the cake.
Topping that stays on topAdding a bit of extra flour to the batter creates a sturdier batter that won’t creep up onto the streusel. Using a springform pan instead of a traditional cake pan means that the cake doesn’t need to be flipped out of the pan, which would disturb the streusel.