Ingredients:
- All-Purpose Flour: 2 3/4 cups (330g) total
- Light Brown Sugar, packed: 1 1/4 cups (250g) total
- Granulated Sugar: 1/4 cup (50g)
- Unsalted Butter: 3 tablespoons (42g) for crumble, plus melted for batter (if substituting oil)
- Ground Cinnamon: 1 1/2 teaspoons total
- Salt: 1/2 teaspoon
- Apples (firm, tart): 1 1/2 cups, peeled, cored, and diced into ½-inch pieces
- Lemon Juice: 1 teaspoon
- Walnuts or Pecans, roughly chopped: 1/2 cup (60g)
- Baking Soda: 1 teaspoon
- Baking Powder: 1/2 teaspoon
- Ground Nutmeg: 1/4 teaspoon
- Large Eggs: 2, room temperature
- Neutral Oil (Canola or Sunflower) or melted Butter: 1/2 cup (118ml)
- Full-Fat Plain Yogurt or Sour Cream: 1/2 cup (120g)
- Pure Vanilla Extract: 1 1/2 teaspoons
Instructions:
- Preheat oven to 350°F (175°C). Grease and flour a standard 9x5 inch loaf pan, or line it with parchment paper, leaving an overhang for easy removal.
- In a bowl, toss the diced apples with 1 teaspoon of cinnamon, 2 tablespoons of granulated sugar, and lemon juice. Set aside.
- Make the Crumble Topping: Brown the 3 tablespoons of butter in a small saucepan until fragrant and nutty brown spots appear. Pour immediately into a bowl to halt cooking. Whisk in 1/2 cup flour, 1/4 cup brown sugar, 1/2 teaspoon cinnamon, and a pinch of salt until coarse crumbs form. Set aside.
- In a large bowl, whisk together the remaining dry ingredients: 2 1/4 cups flour, baking soda, baking powder, nutmeg, and 1/2 teaspoon salt.
- In a separate bowl, whisk the eggs, remaining 3/4 cup brown sugar, and 2 tablespoons granulated sugar until lightened slightly. Whisk in the oil/melted butter, yogurt/sour cream, and vanilla extract until just combined.
- Gently fold the wet ingredients into the dry ingredients until just moistened. Do not overmix; streaks of flour are acceptable.
- Gently fold in the prepared apples and chopped walnuts/pecans.
- Pour the batter into the prepared loaf pan. Sprinkle the reserved brown butter crumble evenly over the top surface of the batter.
- Bake for 55–65 minutes, or until a wooden skewer inserted near the center comes out clean or with moist crumbs attached (not wet batter). If the topping browns too quickly, tent loosely with aluminum foil.
- Cool the loaf in the pan for 15 minutes before carefully inverting it onto a wire rack to cool completely before slicing.