Preheat oven to 350°F.

Place quartered tomatoes and onions on a baking sheet.

Drizzle with vegetable oil.

Sprinkle with the chili powder and cayenne powder.

Place in preheated oven. Bake for 20 minutes. Flip the vegetables over. Cook for 20 minutes more, checking occasionally to make sure the vegetables are not drying out. The vegetables are done when the onions are soft and the skin on the tomatoes is blistery and slightly brown.

Remove from oven and set aside.

Remove the stems and seeds from the chipotles.

Place prepared vegetables and the chipotles in a blender.

Add adobo sauce, garlic cloves, cilantro and lime juice.

Blend to desired consistency - For chunkier salsa, just pulse the blender button for a few seconds. For smoother textured salsa, process longer to get to the consistency you want.

Pour out into a serving bowl or sealable bowl.

Taste. Add salt. to taste. Mix well.

Store, tightly sealed or covered, in the refrigerator, for at least 2 hours to chill and allow the flavors to blend.

Serve cool or at room temperature.