Preheat your oven to 350 degrees.
Combine all the dry ingredients (flour, sugar, ground ginger, baking soda, and salt) in a large bowl.
In another bowl, combine the wet ingredients - oil, sour cream, and egg.
Pour the wet ingredients on to the dry ingredients, then add the diced peaches.
Mix to just bring the batter together. Don’t not over mix the batter. If there are a few lumps don’t worry about it, they will work themselves out.
Place 12 muffin liners into your muffin pan. Distribute the batter evenly in the 12 cups.
Evenly distribute the crumble topping onto each muffin.
Bake for about 20 to 25 minutes, until golden brown on top and cooked all the way through. Remove from pan as soon as you can handle them.