In saucepan put potatoes and salt and water to cover by 1 inch. Bring to boil and simmer on medium until potatoes are just tender, about 20 minutes. Drain and set aside.
In blender puree Aji Amarillo using a small amount of water if necessary. Pour into bowl.
In same blender, add hard-boiled egg and about half of evaporated milk and blend until smooth. Add onion and Sazón and blend until smooth. Continue blending while adding cubes of cheese and remainder of milk, each a little at a time. Use all the cheese and as much milk as needed to make a thick, smooth sauce.
Add pureed Aji Amarillo a little at a time to desired heat level. Add salt and pepper to taste. Sauce should be thick and smooth.
To make the salsa, combine tomato, onion, cilantro and lime juice in bowl. Add salt and pepper to taste just before serving.
Arrange the lettuce leaves on individual plates or one large platter. Place potatoes on lettuce and cover with sauce. Garnish with quartered hard-boiled eggs and whole black olives. Serve with salsa on the side.