For The Oven
Preheat your oven to 425°F (220°C).
Rinse the tomatoes, red onion, and jalapeno peppers. Cut the tomatoes into quarters, peel and quarter the red onion, and remove the stems from the jalapeno peppers. For a milder salsa, remove the seeds and membranes from the jalapeno peppers.
Arrange the tomatoes, red onion, jalapeno peppers, and unpeeled garlic cloves on a baking sheet lined with parchment paper. Drizzle with 1 tablespoon of olive oil and toss gently to coat.
Roast the vegetables in the preheated oven for 20-25 minutes, or until the tomatoes are soft and slightly charred. Keep an eye on the garlic cloves to prevent burning; they may need to be removed earlier.
Remove the baking sheet from the oven and let the vegetables cool slightly. Carefully peel the roasted garlic cloves.
In a food processor or blender, combine the roasted tomatoes, red onion, jalapeno peppers, and garlic cloves. Pulse until the mixture reaches your desired consistency, from chunky to smooth.
Transfer the salsa to a bowl and stir in the chopped fresh cilantro, fresh lime juice, and the remaining 1 tablespoon of olive oil. Season with salt to taste.
Let the salsa sit for at least 30 minutes at room temperature to allow the flavors to meld. For best results, cover and refrigerate for a few hours or overnight before serving.
For The Gas Stove
Preheat a gas stove top flame to medium-high heat. Place the tomatoes directly on the flame, turning occasionally with tongs, until the skin is charred on all sides. This should take about 5-7 minutes.
Remove the tomatoes from the heat and allow them to cool for a few minutes. Once cool enough to handle.
Char garlic, jalapeños, and onion.
Add the chopped cilantro, lime juice, olive oil, and salt and to taste. Mix everything together with the charred veggies in a blender until well combined.
Serve the tomato salsa dip immediately with tortilla chips, or use it as a topping for tacos, burritos, or any other dish that could use a little extra flavor and spice.