Preheat oven to 350 degrees. Butter 4 (6-inch) cast iron skillets (or a 10-inch skillet or 9-inch round or square pan).

With an electric mixer, cream 1/2 cup butter and 1/2 cup brown sugar until light and fluffy.

Beat in the egg and vanilla. Add the baking powder and salt and mix well.

Add the flour and mix until just moistened. With the blender on low speed, gradually add the buttermilk and mix until smooth.

Make the streusel by combining the flour, sugar and spices in a small bowl. Cut in the butter until the mixture resembles course crumbs.

Divide the batter evenly between the skillets, or spread evenly into a single pan. Sprinkle the strawberries over the batter, then top the berries with the streusel.

Bake 25-30 minutes for individual skillets (40-45 minutes for a larger pan or skillet) or until the top is a light golden brown. Let stand 5 minutes before serving.