Preheat the oven to 350 degrees F (180 degrees C).
Cut the Marzipan (7 ounce) into 1/2-inch pieces and toss with the Powdered Confectioners Sugar (1 tablespoon). Set aside.
In a medium bowl, whisk together the All-Purpose Flour (3 1/4 cup), Baking Powder (1 teaspoon), and Kosher Salt (3/4 teaspoon).
In a large bowl, whisk together the Granulated Sugar (1 cup) and Neutral Oil (1 cup) until combined. Whisk in the Large Egg (3) one at a time, and then whisk in theVanilla Extract (2 teaspoon) and Almond Extract (1/2 teaspoon), if using.
Use a wooden spoon to gradually mix in the flour mixture, marzipan, and Cacao Nibs (1/2 cup). This dough can be made the night before and stored in the refrigerator until ready to use.
Line a baking sheet with parchment paper. Divide the dough into 2 equal portions and place on the lined baking sheet. Mold the dough into two 14x3-inch rectangles about 3 inches apart.
Sprinkle the tops with a few pinches of Sea Salt Flakes (to taste) and Sprinkles (to taste).
Bake until the centers are set and the bottoms are lightly browned, 25 to 30 minutes. Remove from the oven and reduce the oven temperature to 250 degrees F (120 degrees C).
Let the mandel bread cool slightly and then use a sharp serrated knife to cut crosswise into 1-inch thick slices. Turn the slices on their sides and bake for 20 more minutes, or until desired crispness.
Let cool slightly and enjoy with coffee, hot chocolate, or tea. Enjoy!