In a large bowl, combine the flour, baking powder, mustard and cumin. In another bowl, whisk eggs and buttermilk. Stir into dry ingredients just until moistened. Fold in ham and 1-1/4 cups cheese.
Fill greased muffin cups two-thirds full. Sprinkle with remaining cheese. Bake at 375° for 20-25 minutes or until a toothpick comes out clean. Cool for 5 minutes before removing from pans to wire racks. Serve warm. Refrigerate leftovers.