Stir together 2 cups all-purpose baking mix, 1 cup milk, 1/2 cup sugar, and 2 large eggs in a large mixing bowl, stirring just until dry ingredients are moistened. Stir together 1/2 cup chunky peanut butter and 1/2 tsp. vanilla just until blended; stir in 1 cup semisweet chocolate morsels. Spoon batter into lightly greased paper-lined muffin pans, filling two-thirds full.
Bake at 350 for 24 minutes or until lightly browned.
Remove from pans; serve warm.
Note: For testing purposes only, we used Bisquick Original All-Purpose Baking
