SANTA MONICA. For seafood done Mexican style, try this Santa Monica favorite. Regulars attest to the fact that the consistent presentation of the expertly prepared seafood dishes have made them steadfastly loyal. Order the fish quesadilla, the shredded beef in red chile sauce, or the chicken enchiladas. Excellent margaritas round out the experience. The décor is done in warm tones and features carved stone pillars and a lovely fountain. An upscale casual atmosphere pervades.