Granted the waitstaff isn't wearing sombreros and the music blaring on the sound system is an odd mix of merengue, salsa, and upbeat rock en espa?ol. But the requisite cowboy memorabilia clinging to the walls, plus the basket of freshly made chips, tart salsa, and giant margaritas on the table, are enough to tell you there's a definite Tex-Mex vibe in the air. Founded in 1982 in Dallas, the wildly successful On the Border was acquired in 1994 by casual-dining company Brinker International, owner of other popular eateries including Chili's Grill & Bar and Romano's Macaroni Grill. More than 100 outposts now stretch across the country, offering consistently tasty Mexican fare in generous portions. Among the abundant appetizers: smoked chicken flautas served with chili con queso and firecracker stuffed jalape?os filled with chopped chicken and cheeses. Main-dish choices range from burritos, chimichangas, and enchiladas to mesquite-fired fajitas boasting sizzling chicken, shrimp, beef, or portobello mushrooms. Remnants of spiciness can be soothed by a sinful sweet, be it Kahlua ice cream pie, Mexican crème caramel, or apple and strawberry chimichangas.