I googled this up because I've never heard of Pollo con Crema - it sounds very good! So, this is the recipe I found, it is most definitely not tried and true. You'd have to do some substituting with low fat cheese and maybe fat free half and half, I suppose.

Title: Recipe: Pollo Crema (like Azteca's Pollo a La Crema)
Board: International Recipes at Recipelink.com
From: Gladys/PR 5-12-2006
To: ISO: pollo con crema
MSG ID: 0310172

Pollo Crema (like Azteca's Pollo a La Crema)
Source: Julesong

Note from Source: This is my take on Azteca Restaurant's Pollo a la Crema. Rich and delicious! Chicken breast, sautéed with onion in a delicious mild crema sauce. Although the ingredient list is long, this recipe is actually quite easy to put together.

6 boneless skinless chicken breasts, cut into strips (or bite sized pieces)
1 medium fresh sweet onion, sliced (yellow or red onion, your preference)
2 tablespoons vegetable oil
3 cups boiling water
2 teaspoons beef bouillon granules
1 teaspoon chicken bouillon granules
6 ounces tomato paste
2 teaspoons minced roasted garlic
1 tablespoon dried ancho chile powder
1 teaspoon cumin
1/2 teaspoon cocoa powder
1/4 teaspoon cider vinegar
1 teaspoon dry sherry
1/4 teaspoon butter
1/2 teaspoon Tabasco sauce or your favorite hot sauce, to taste
1 cup Mexican crema (Mexican "Table Cream")
salt & freshly ground black pepper, to taste
1/4 cup crumbled Cotija cheese, for garnish (also known as Queso Anejado, can substitute feta if necessary)
chopped scallions, for garnish
1 ripe avocado, pitted, peeled, and cut into slices, for garnish

In a large skillet, heat the oil over medium temperature then sauté the sliced onion until it begins to soften, about 3 to 5 minutes.

Add the chicken and sauté until browned, stirring occasionally, about 7 minutes.

In another large saucepan over medium heat, stir together the boiling water and bouillon granules until dissolved.
Add remaining ingredients (except for garnish) and the cooked chicken and onion, stir well, and simmer for 5 minutes.

Garnish with crumbled Cotija, a bit of chopped scallion, and avocado, serve with rice and beans, and enjoy!

Note: to make the sauce even better, instead of the bouillon granules and water use 2 cups homemade beef stock and 1 cup homemade chicken stock.

Servings: 6

Oh, I meant to add low fat sour cream as a substitute - something I read said that they use a Mexican creme fraiche - and I would think that low fat sour cream might be an acceptable substitute in a dish like this.

I hope that someone comes up with something for you!