Preheat the oven to 375 degrees F and prep a muffin tin with liners.
Combine all the dry ingredients in a large bowl. In a smaller bowl, whisk together the wet ingredients except carrots, raisins, walnuts.
Add the wet ingredients to the dry ingredients and stir together. Add the carrots, walnuts and raisins. Gently stir until just combined.
Spoon the batter 2/3 of the way up into the muffin liners.
Make the crumble:
Combine the flour, oats, and brown sugar. Melt the butter and add the maple syrup. Stir in the butter and maple syrup and mix with a fork. Using your fingers, gently crumble the mixture to the top of the muffin.
Bake at 375 degrees F for 22 minutes until toothpick comes out clean.