Preheat your oven to 425°F (220°C). Line a baking sheet with parchment paper.
In a large mixing bowl, whisk together the flour, baking powder, garlic powder, onion powder, salt, and black pepper until well combined.
Stir in the shredded cheddar cheese, mixing until the cheese is evenly distributed in the flour mixture.
In a separate bowl, combine the melted butter and buttermilk. Pour the wet ingredients into the dry ingredients and mix until just combined.
Gently fold in the cooked crab meat until evenly distributed, being careful not to overmix.
Using a cookie scoop or spoon, drop heaping tablespoons of the biscuit dough onto the prepared baking sheet, spacing them about 2 inches apart.
Bake in the preheated oven for 15-20 minutes, or until the biscuits are golden brown on top and cooked through.
While the biscuits are baking, prepare the lemon butter sauce. In a small saucepan over medium heat, melt the butter. Remove from heat and stir in the lemon juice, lemon zest, and salt.
Once the biscuits are done, drizzle the lemon butter sauce over them while they are still warm. Optionally, sprinkle with chopped parsley for garnish.