Tequila-Chipotle Shrimp

In a large skillet, heat the oil. Add the onion and chipotle and cook over moderately high heat, stirring, until just starting to soften, 2 to 3 minutes. Add the tomatoes and bring to a simmer. Season with salt and pepper, then nestle the shrimp in the sauce and cook, turning once, until just white throughout, about 5 minutes. Stir in the pineapple and tequila, garnish with cilantro and serve right away.