Ensure that the oven temperature is 350 degrees Fahrenheit.
Prepare a baking sheet by cutting tomatoes and onions into four parts and drizzling with vegetable oil.
For seasoning, add some chili and cayenne pepper, then bake at 350 degrees Fahrenheit for 30 to 35 minutes.
Halfway through the cooking process, flip the vegetables over.
Keep an eye on the vegetables from time to time to make sure they don't dry out.
With tongs or a spatula, move the excess oil around on the sheet.
In order to finish, the skin needs to be blistered, supple, and somewhat brown in color.
The stems and seeds of the chipotles need to be removed.
All the prepped vegetables, cilantro, and garlic should be blended in a blender. Chipotle should also be added.
Blend the ingredients until smooth after you squeeze the lime juice into the blender.
Place it in a bowl or jar and let it cool.