“We should make these 1,000 times.” — David, recipe tester, age 5
GREASE: Spray inside bottom and sides of 8-inch square metal baking pan well with vegetable oil spray. Spray rubber spatula with vegetable oil spray.
MELT: In large bowl, combine marshmallows, butter, vanilla, and salt. Heat in microwave until marshmallows are puffed, about 2 minutes. Use greased rubber spatula to stir until smooth.