How to Make It
In a large nonreactive skillet, cook the onion in the olive oil over moderate heat, stirring occasionally, until translucent, about 5 minutes. Add the garlic and the jalapeño and cook until the garlic becomes a pale gold. Stir in the parsley, then add the tomatoes with their juices and liberal pinches of salt. Reduce the heat and cook at a steady simmer, stirring occasionally, until the tomatoes cook down and the oil begins to separate from the sauce, about 20 minutes.
Add the shrimp to the skillet and stir to coat with sauce. Cover and simmer until the shrimp are just cooked through, 2 to 3 minutes. Season with additional salt and serve immediately with the grilled bread.