1. Preheat oven to 350 degrees Fahrenheit. Grease muffin tins.
2. For the batter: In a bowl, mix dry ingredients well with a whisk. Add wet ingredients and mix until the batter is smooth. Pour into muffin tins and place in the oven for 10 minutes.
3. Meanwhile, prepare the crumb ingredients: In a medium bowl, combine all the ingredients and mix until crumbly.
4. After muffins are in the oven for 10 minutes, take them out and place crumbs on top of the half-baked muffins. Place back in the oven for another 10 minutes or until done.