Place sesame seeds in a large skillet over medium heat, stir frequently until seeds begin to darken in color. Do not burn. Remove immediately from heat and transfer to a bowl.

On the same skillet, place guajillo chile, arbol chile and garlic clove over medium heat. Heat for 2 minutes, roasting dried chiles on all sides and a few char spots for. Turn off heat. Remove garlic clove and set it aside.

Add hot water to pan and let dried chiles soak for 15 minutes.

Place hydrated chiles, garlic clove and 1 ½ cups water chiles soaked in into a high-power blender. Blend for 1 minute. Add cumin and blend for another minute.

Wipe skillet clean with a paper towel. Add oil and heat over medium heat. Add onion and cook for 1 minute or until fragrant. Carefully pour in sesame seed mixture and season with salt. Boil for 5 minutes stirring frequently. Turn heat off.

Fold corn tortilla in half and place in sauce. Spoon sauce over folded tortilla and transfer to a serving dish. Repeat with 2 more tortillas. Top with crema and queso fresco. Serve with rice.