Fried Squid with Aioli

Name: Fried Squid with Aioli
Ingredients: 2/3 cup potato starch; 1 1/4 teaspoons baking powder; 1 3/4 cups arepa flour (precooked cornmeal), divided; 1 large egg yolk; 1 garlic clove, finely grated; 1 teaspoon fresh lemon juice; 1/2 cup grapeseed oil; 1/4 cup olive oil; Kosher salt; Vegetable oil (for frying; about 8 cups); 6 ounces cleaned squid, bodies and tentacles separated; 4 scallions, white and pale-green parts only, sliced into 3-inch pieces; 4 very thin lemon wheels; 1/3 cup torn basil leaves; A deep-fry thermometer