Preheat oven to 350°. Melt butter and add to sugar. Beat in eggs one at a time. Add flour, salt and almond extract; mix well. Line cast iron skillet with aluminum foil extending up over sides. Pour batter into lined skillet. Combine almonds and sugar and sprinkle on top of batter. Bake at 350° 30 to 40 minutes, allow to cool, remove from skillet and foil. Slice and serve warm.