In a large bowl whisk together the almond flour, baking powder, and ½ teaspoon xanthan gum.
Grate the frozen (or very cold) butter. Mix into the flour mixture with a fork until it resembles coarse crumbs. Set aside.
In a separate medium size bowl beat the egg whites to stiff peaks.
Gently fold the egg whites into the flour mixture with a rubber spatula until just combined.
Chill the biscuit mixture in the refrigerator while making the gravy.
In a large skillet brown the sausage over medium heat.
Remove the sausage to a paper towel lined plate to drain the excess grease, reserving about a tablespoon of fat in the skillet.
Turn the heat to medium-low and sprinkle 1 teaspoon of xanthan gum into the grease, whisking constantly.
Cook the xanthan gum for about a minute until lightly browned.
Whisk in the chicken stock, onion powder and black pepper. Bring to a simmer and allow the gravy to thicken, about 5 minutes. Taste at this time and add salt if needed.
Whisk in the half and half and continue to simmer until the gravy is thick and creamy, about another 3 minutes.
Stir the cooked sausage into gravy and remove from the heat.
Preheat the oven to 375°F degrees.
Pour the sausage gravy into an 8x8 casserole dish.
Drop the biscuit mixture on top of the gravy in small spoonfuls, distributing as evenly as possible. The mixture will be thick.
Bake for 18-20 minutes until hot, bubbly, and the biscuits are baked and browned.