Preheat broiler.

To a baking sheet add the tomatoes, onion and jalapeño. Drizzle lightly with vegetable oil

Broil until the vegetables until they get slightly charred. Remove and allow to cool.

When the jalapeno is cool enough, cut in half and remove the stem and seeds.

Add the tomatoes to a food processor and pulse 3 times. Add the onion, jalapeño, cilantro and salt. Blend until it reaches your desired consistency. Taste for salt, add more if needed.