Start by cleaning the soft-shell crabs, removing the gills and the skirt flap. Refrigerate until ready to cook. On the stove, over medium heat slowly bring the vegetable oil to 325 degrees. Then lower the heat to hold the temperature. While the oil is heating prepare the buttermilk by mixing in the grated lemon zest and season with salt and pepper. In a shallow pie tin combine the flour and the Old Bay seasoning. The correct way to batter using flour is a method known as dry-wet-dry, so start by coating the crabs with the seasoned flour then dredging them into the buttermilk and then back into the flour. Carefully using tongs drop the crabs into the oil and fry until crisp, when golden brown, remove from oil and drain on a paper towel. Serve the crabs in a basket with French fries, coleslaw, grilled corn, tartar sauce, and lemon. Another delicious serving method is to eat on white toasted bread with lettuce & tomato and mayonnaise.