Adjust oven rack to upper third of oven and preheat to 425 degrees F. Line a baking sheet with silicone baking mat or spray with nonstick cooking spray.
FOR THE BISCUITS:
Add flour, baking powder, sugar, Old Bay seasoning, and salt to the bowl of a food processor and pulse to combine. Slowly add shortening and butter and pulse 5-6 times until mixture is in pea-sized pieces. Add cheese and pulse 1-3 times until mixed. Pour in milk and pulse until dough comes together, about 6-8 pulses.
Using a ¼ cup scoop, place dough on prepared baking sheet, 2-inches apart. Lightly compress biscuits with the palm of your hand. Bake until golden brown, about 15-18 minutes.
FOR THE GARLIC BUTTER:
Add butter and garlic to a small saucepan over medium heat. Cook until melted, about 1 minute. Remove from heat and stir in parsley.
Brush biscuits with butter mixture and serve warm.