Arrange tomatoes and jalapeños on a lightly greased baking sheet; broil 5 1/2" from heat 10 to 15 minutes or until lightly charred and blistered, turning once or twice. Transfer jalapeños to a bowl, and let cool. Place tomatoes in a large zip-top plastic bag; seal and let stand 10 minutes.
Combine onion, garlic, and olive oil in a bowl; transfer to a baking sheet. Bake at 450° for 10 minutes, stirring once, until golden and soft.
Remove stems from jalapeños, and transfer whole peppers to a food processor. Add onion and garlic; process until finely chopped, scraping down sides of bowl. Transfer mixture to a bowl.
Peel tomatoes over a bowl to catch juices. (Do not seed.) Transfer peeled tomatoes to food processor; process until coarsely chopped. Add to jalapeño mixture, stirring well. Stir in tomato juice and remaining ingredients. Store in an airtight container in refrigerator up to 2 days. Serve salsa at room temperature.