Browned Butter-Plum Muffins

Muffins

• 1/2 cup butter (do not use margarine)
• 2 large plums, coarsely chopped (2 cups)
• 1/4 teaspoon ground cardamom
• 1 1/2 cups Gold Medal™ all-purpose flour
• 3/4 cup granulated sugar
• 1 1/2 teaspoons baking powder
• 1/2 teaspoon salt
• 1/3 cup milk
• 1 teaspoon vanilla
• 2 eggs, slightly beaten

Streusel Topping

• 1/2 cup packed brown sugar
• 1/2 cup chopped walnuts, toasted
• 1/4 cup butter or margarine, softened
• 1/3 cup Gold Medal™ all-purpose flour