For Muffins • 2 cups all-purpose flour (250g) • ½ cup light brown sugar packed (100g) • ¼ cup granulated sugar (50g) • 2 teaspoons baking powder • 1 teaspoon ground cinnamon • ½ teaspoon table salt • ½ cup canola oil (120ml) • ½ cup buttermilk (120ml) • 2 large eggs lightly beaten • 1 ½ teaspoons vanilla extract • 1 ½ cups peeled chopped apples (215g)

For Crumb Topping • 1 ¼ cups all-purpose flour (156g) • ½ cup light brown sugar packed (100g) • ⅓ cup granulated sugar (66g) • ½ teaspoon ground cinnamon • ¼ teaspoon table salt • 6 Tablespoons unsalted butter melted but cooled so no longer warm to the touch (85g)

Wash and peel apples before chopping them into small cubes.

In a large mixing bowl, whisk together flour, sugars, baking powder, cinnamon, and salt.

In a separate bowl (or large measuring cup), whisk together oil, buttermilk, eggs, and vanilla extract until well-combined.

Add the wet ingredients to the dry ingredients and use a spatula or spoon to gently stir ingredients together until approximately 50-75% combined. 

Make the crumb topping... In a medium-sized bowl, whisk together flour, sugars, cinnamon, and salt.

Drizzle melted butter over the flour mixture and use a fork to toss/claw the mixture together until all of the dry ingredients are moistened and you have a crumbly streusel.

Preheat oven to 375F (190C) and line a 12-count muffin tin with paper liners. 

Evenly divide streusel over the muffins.

Transfer to center rack of 375F (190C) oven and bake for 24-25 minutes or until a toothpick inserted in the center comes out clean. Allow to cool 10 minutes before enjoying.