Core the tops of the tomatoes. Slice the onions in half, but leave the root ends in tact until after boiling.
Fill a large saucepan about halfway with water. Add the tomatoes, onions, peppers and 4 of the garlic cloves. Bring to a boil for about 10 minutes or until the tomatoes are tender, adding more water if needed.
Remove the vegetables with a slotted spoon and let cool. Peel the outer skin of the tomatoes off and discard (soaking them in cold water beforehand, will release the skin easier). Cut the stems off the jalapeno and serrano peppers, and remove the seeds, if desired. Remove the root ends of the onions.
Add all the vegetables, along with the remaining 2 garlic cloves, guajillo peppers and Salt and pepper, to taste to a blender. Blend until smooth.
Pour the contents in a saucepan and bring to a boil. Reduce the heat to a simmer, cover and continue to cook for 10 minutes, stirring occasionally.
Meanwhile, heat about 1 tablespoon of bacon grease or oil in a cast iron skillet. Add the tortillas and flip to coat with grease on both sides. Cook until they bubble up slightly and warm through on both sides. Be sure not to overcook until crispy.
Return to the skillet, adding more grease if needed, and add the egg(s) until they are over-easy.
Take the tortillas and top with the egg followed by some sprinkled cheese and then the sauce. Top with more cheese, if desired. Serve immediately.
