In a sauce pot, sauté the onions and chopped garlic in olive oil until translucent, stirring. Add ketchup, tomato paste, orange juice, white wine vinegar and honey to mixture, and cook, stirring, for 10 minutes. Remove from heat and puree in a blender (take care to leave an opening in the lid to allow steam to escape). Return the sauce to the pot and keep warm and pour over chicken and enchiladas.
To prepare chicken breasts:
Combine the lemon zest, cilantro, olive oil, pepper and salt in a mixing bowl, add the chicken, and toss to coat well. Marinate chicken for 1 hour at room temperature. Meanwhile, preheat a grill to the white coal stage. After one hour marinating, transfer chicken breasts to a cookie sheet lined with paper towel.
Transfer chicken to hot grill and cook for 10-15 minutes, turning once or twice, to cook the meat evenly. Reserve grilled chicken on the cookie sheet while making the enchiladas and sauce.
To prepare enchilada:
Heat a sauté pan to medium. Add the olive oil, swirl to heat, then add the onions and sauté for one minute, stirring. Add the mushrooms and potatoes, sauté for an additional 3-5 minutes. Then add 1 cup of cooked meat from the chicken legs and sauté for another minute. Season with salt and pepper to taste and then add cilantro. (If you find the filling is a little dry, you can add some low-sodium chicken broth. Reserve over warm.
Brush both sides of each corn tortilla with olive oil and heat in a large sauté pan over warm until tortilla becomes pliable. Transfer tortilla to a cutting board, add a few tablespoons of filling to the center, and roll up like a cigar, to close.
Place enchilada on warm plate, and continue with remaining tortillas and filling until all the ingredients have been used. Slice grilled chicken breast with the grain, and arrange slices on top of enchiladas.
Top with sweet jalapeño sauce and serve with a little grated Monterey jack cheese over the top and sour cream on the side.