Heat oven to 350°F. Grease a 9x5-inch loaf pan and line with parchment paper so the two long sides have at least an inch hanging over that you can use as handles to pull the loaf out of the pan once it is baked.
Place the 3/4 cup hazelnuts in the bowl of a food processor and pulse until they are finely ground into a flour, but not so much that they become a paste.
In a medium bowl, whisk together the ground hazelnuts, the 1 cup flour, the 3/4 cup brown sugar, the 2 teaspoons baking powder, the 1 teaspoon baking soda, 1 teaspoon of the cinnamon, the 1/2 teaspoon kosher salt and the 1/4 teaspoon nutmeg.
In a separate large bowl, whisk together the 2/3 cup milk, 1/2 teaspoon vinegar, 1/3 cup oil, 1 teaspoon vanilla, and 2 eggs until smooth. Mix the dry ingredients into the wet with a silicone spatula just until combined. Then and add the 1 cup grated apples, 1 cup grated carrots and half of the chopped pecans. Fold to mix thoroughly.
Pour batter into the prepared pan. Combine remaining half of the pecans, 1/2 teaspoon cinnamon, and 2 tablespoons coarse sugar. Sprinkle on top of the bread using all of the topping.
Bake for 50-60 minutes or until a skewer inserted in the center comes out with a few moist crumbs. Bread will form a crisp crust but be moist in the middle. Let cool in the pan for 15 minutes then pull the bread out by the overhanging parchment paper onto a cooling rack to cool at least 15 minutes longer before slicing.