2 medium sweet apples, washed, cored, and grated (not peeled)
1 teaspoon pure vanilla extract
Instructions
Preheat oven to 400F; line 2 muffin trays with 20 to 24 paper liners (or butter and flour the muffin wells).
For the crumble topping, use a fork to cut together the biscoff spread and brown sugar in a medium bowl. Mix in the vanilla, then the flour, oats, cinnamon, and salt until the mixture resembles coarse meal with some pieces the size of peas.
For the muffins, whisk together the flour, oats, baking powder, cinnamon, salt, baking soda, nutmeg, and cardamom in a medium bowl. Beat together the eggs and brown sugar in a large bowl, then cream in the biscoff spread; stir in the milk, yogurt, apples, and vanilla. Pour the dry ingredients into the wet all at once and stir just to combine, being very careful not to over-mix (a few lumps or streaks of flour are fine).
Fill each muffin well about ⅔ full with batter, then divide the crumble topping on top. Bake until a toothpick inserted inside comes out clean but still moist, about 18 to 20 minutes.