To make the aioli: beat cream in a small bowl with a whisk until stiff peaks form. Fold in remaining ingredients until blended. Cover mixture and chill. Store leftovers in an airtight container in refrigerator for up to 3 days.
In a small bowl combine all of the spices. Press a heaping tablespoon of the spice mix onto each fillet so that both sides are liberally coated. Allow the fish to sit for 15 minutes at room temperature prior to cooking.
In a large skillet, heat the oil over medium-high heat. Once the oil is almost smoking, add the fillets and cook for 2 to 3 minutes on each side. Sprinkle with lemon juice or a dollop of Lemon Aioli.