Rhubarb Streusel Muffins

1/2 cup butter, softened

1 cup packed brown sugar

1/2 cup sugar

1 egg

2 cups flour

1 teaspoon baking powder

1/2 teaspoon baking soda

1/8 teaspoon salt

1 cup (8 ounces) sour cream

3 cups chopped fresh or frozen rhubarb, thawed

Topping:

1/2 cup chopped pecans

1/4 cup packed brown sugar

1 teaspoon ground cinnamon

1 Tablespoon cold butter

In a large bowl, cream butter and sugars until light and fluffy. Beat in egg. Combine the flour, baking powder, baking soda and salt; add to creamed mixture alternately with sour cream, beating well after each addition. Fold in rhubarb. Fill paper-lined or greased muffin cups three-fourths full. For topping, combine the pecans, brown sugar and cinnamon in a small bowl; cut in butter until crumbly. Sprinkle over batter. Bake at 350 degrees for 22-25 minutes or until a toothpick inserted near the center comes out clean. Cool for 5 minutes before removing from pans to wire racks. Serve warm.