Prep the pan and oven: Heat the oven to 350°F (175°C).
Line a 9x5-inch loaf pan with parchment, leaving overhang for easy lifting, and lightly grease the sides.
Chop the apples: Peel if you like, then core and finely dice 1–1.5 cups of apples. Toss with a squeeze of lemon juice if you’re prepping ahead.
Mix dry ingredients: In a large bowl, whisk 1 1/2 cups almond flour, 1 cup oat flour, 1 1/2 teaspoons baking powder, 1/2 teaspoon baking soda, 1 teaspoon cinnamon, a pinch of nutmeg, and 1/2 teaspoon salt until no clumps remain.
Whisk wet ingredients: In a separate bowl, whisk 2 large eggs, 1/2 cup unsweetened applesauce, 3 tablespoons maple syrup, 3 tablespoons oil, and 1 teaspoon vanilla until smooth and slightly frothy.
Combine: Pour wet ingredients into the dry. Stir with a spatula just until combined.
The batter will be thick but spreadable.
Fold-ins: Gently fold in the diced apples and, if using, 1/3 cup chopped nuts and 1/4 cup raisins. Don’t overmix.
Fill the pan: Scrape batter into the prepared loaf pan and smooth the top. For a pretty finish, sprinkle a little extra cinnamon on top.
Bake: Bake 45–55 minutes, until the top is golden and a toothpick inserted in the center comes out clean or with a few moist crumbs.
If the top browns too fast, tent loosely with foil for the last 10 minutes.
Cool properly: Let the loaf cool in the pan for 10–15 minutes, then use the parchment to lift it to a rack. Cool at least 45 minutes before slicing. This helps the crumb set.
Slice and enjoy: Use a sharp serrated knife for clean slices.
Serve warm or at room temperature.