In a small bowl, combine the first five ingredients. Whisk the egg, milk, butter and espresso powder until espresso powder is dissolved. Stir into the dry ingredients just until moistened. Fill greased or paper-lined muffin cups two-thirds full.
For topping, combine the flour, sugar and cinnamon. Cut in butter until mixture resembles coarse crumbs. Sprinkle about 1 teaspoon over each muffin.
Bake at 400° for 18-20 minutes or until a toothpick comes out clean. Cool for 5 minutes before removing to a wire rack. Serve warm.