Move oven rack to middle position and heat oven to 450°F. Line a baking sheet with parchment paper or a silicone pan liner.
In a large bowl, whisk together whole wheat and all purpose flours, baking powder, baking soda, sugar, and salt. In a medium bowl, or large measuring cup, stir melted butter into buttermilk until the butter hardens and forms small clumps.
Stir the buttermilk mixture into the flour mixture with a rubber spatula until just combined.
Use a measuring cup or scoop to scoop batter in 1/4 cup portions onto the prepared baking sheet. You should end up with 12 biscuits. Bake until the tops are golden brown, 12-14 minutes. Cool at least 10 minutes before serving.
Homemade Turkey Sausage
Mix ground turkey, brown sugar, sage, salt, black pepper, and red pepper flakes together in a large bowl until well combined. Store in an airtight container and refrigerate until ready to use.
Sausage Gravy
Cook turkey sausage in a large, non-stick skillet over medium-high heat until well browned.
While sausage is cooking, whisk together flour, pepper, salt, garlic powder, and cayenne in a small bowl. When the sausage is browned, sprinkle flour mixture over the top of the browned sausage and stir. Continue to cook for 2 minutes, stirring frequently.
Very slowly pour the milk over the sausage mixture, stirring constantly while pouring (the milk will bubble and thicken). After all the milk has been added, bring the mixture to a boil. Reduce heat to medium, and simmer until the gravy has thickened, about 3-4 minutes. Serve immediately over warm biscuits.