NOTE: OLD BAY WITH LEMON & HERB SEASONING IS OFTEN DISPLAYED BY FISH AND SEAFOOD IN MOST MAJOR U.S. SUPERMARKET CHAIN BUTCHER DEPARTMENTS (SAFEWAY, ETC.). PLACE oven rack in center position; PREHEAT oven to 450°F.
MEASURE 2 cups Bisquick, then 1/2 tablespoon yellow masa harina into a medium bowl; GRATE 2 tablespoons of cold firm butter using a cheese shredding grate; BLEND baking mix and butter mixture until coarse and crumbly; GRATE 1/2-3/4 cup shredded medium-sharp cheddar cheese into mixture in bowl without stirring (NOTE: DO NOT ADD TOO MUCH CHEESE OR BAKED BISCUITS WILL SCORCH).
BLEND 1/4 teaspoon garlic powder into 2/3 cup milk; POUR mixture all at once over Bisquick and cheese in bowl; STIR ingredients just until a soft dough forms, without overmixing.
DROP 9 evenly portioned spoonfuls of dough evenly on baking sheet.
SEPARATE one egg, reserving the white in a small bowl; WHISK 3 tablespoons water into the bowl for the BEFORE-BAKING BASTE; BRUSH the dough lightly and evenly with this mixture.
BAKE biscuits on the center rack at 450°F between 8-10 minutes or until golden brown; PROCEED to the next step while biscuits are baking.
ADD 1/4 cup margarine or butter into a small microwave-safe bowl; MICROWAVE on 100% power for 40 seconds; STIR in the following BASTE ingredients: 1/2 teaspoon garlic powder, 1/4 teaspoon Old Bay Lemon & Herb Seasoning, 1/4 teaspoon lightly crushed dried parley flakes, and 1/8 teaspoon Accent seasoning.
REMOVE baking sheet with biscuits from oven; TURN oven off.
BRUSH tops of each baked biscuits generously with the AFTER-BAKING BASTE; RETURN baking sheet with basted biscuits to the cooling oven just long enough for baste to "bake" into biscuits (with oven OFF).