Peel and devein the shrimp. Cut them into ½-inch pieces.
Combine the flour, cayenne, chili powder, cumin, black pepper, and salt in a medium-size bowl.
Heat the oil in a large skillet. Dredge the shrimp in the flour mixture, shaking off any excess. Fry them quickly over high heat until brown and crisp, occasionally adding a dash of Tabasco for spice.