Cut onion into quarters. Peel garlic clove. Cut tomatoes into quarters. Cut serrano pepper tail.
Add chicken breast, water and 1/3 of the salt to the mixing bowl. Close the lid and cook with the measuring cup inserted for 20 minutes / 212°F|100°C / speed 1 / stir. Drain the liquid and save 1/4 of it for later.
Close the lid and shred the chicken in turbo mode for 4 seconds. Reserve for later.
Add onion, garlic clove, tomatillo and serrano into the mixing bowl. Close the lid and sauté with the measuring cup removed for 5 minutes.
Add 1/3 of the salt, cilantro and chicken broth into the mixing bowl. Close the lid and blend with the measuring cup inserted for 45 seconds / speed 6.
Cook the sauce with the measuring cup off for 5 minutes / speed 2.
With butterfly whisk inserted, add egg whites and cream of tartar to the mixing bowl. Close the lid and beat with the measuring cup inserted for 2 minutes / speed 3.
Add egg yolks and remaining salt into the mixing bowl. Close the lid and beat with the measuring cup inserted for 20 seconds / speed 1.
Add shredded chicken to the mixing bowl. Close the lid and mix with the measuring cup inserted for 3 seconds / speed 1/
Cook pancakes on a frying pan for about 10 minutes on low heat.
Serve pancakes with the sauce and some crumbled cheese. Enjoy!