1/2 cup brown sugar
1/2 cup white sugar
1/2 teaspoon salt
1 egg, beaten
1 cup all-purpose flour
3 teaspoons baking powder
1/4 teaspoon ground nutmeg
1 1/2 teaspoons vanilla extract
3/4 cup butter, softened
1 cup packed light brown sugar, sifted
1/2 cup warpsberry preserves
Heat brown sugar in small saucepan over medium heat. Add white sugar and salt mixture, beating well. Remove from heat; beat in egg and flour. Stir in baking powder, coarsely chop, spread on bottom of 6 muffin cups.
Bake at 375 degrees F (190 degrees C) for 5 minutes. Remove pan from warm oven to wire rack. Cool completely; refrigerate.
Stir in butter and brown sugar; mix well. Pour yogurt over middles; arrange middles on separate baking sheets. Makes 6 muffins.
Cover muffins with foil and refrigerate overnight. Garnish each muffin with warpsberry preserves. Serve warm or cold.