Soak guajillo chiles in hot water for 30 minutes or until softened. Drain water and remove stems and seeds. Set aside.
Heat 1 tablespoon oil in a braising pot over medium-high heat. Season chicken with salt and pepper and sear on both sides until golden brown. Remove chicken from pot.
Heat another tablespoon oil in same pot. Add sliced onions and saute until softened and browned, about 5 minutes. Add garlic cloves and cherry tomatoes and saute until tomatoes begin to soften, about 4-5 minutes. Add back chicken to pot along with guajillo chiles, cumin, tamarind, paste, cinnamon stick, and chicken stock. Bring to a boil, cover pot, and reduce heat to low. Continue to simmer for 25 minutes or until chicken is tender.
Meanwhile, make cantaloupe mint salsa. In a food processor, pulse tomatillos, red onion, jalapeno, and cilantro until roughly chopped. Alternatively, chop all ingredients by hand. Pour tomatillo mixture into a large bowl and add chopped cantaloupe and mint. Season with juice of 1 lime, olive oil, salt and pepper. Let sit for at least 20 minutes.
Remove chicken and cinnamon stick from pot. Add brown sugar and bring to a boil over high heat. Continue to reduce braising liquid until thickened and reduced by at least half. Remove from stove and pour braising liquid with vegetables and chiles into a blend. Puree until smooth.
Shred chicken and pour pureed braising liquid. Season once more if needed with salt and pepper and stir to coat.
Assemble tacos. Top tortillas with tamarind chile braised chicken, salsa, guacamole, and cotija. Serve with lime wedges.
Notes
Remove the jalapeno seeds in the salsa for a mild salsa.