Season the chicken cutlets with salt and pepper. In a large skillet over medium-high heat, melt 2 tablespoons of the butter and add the chicken to the skillet, spreading it into an even layer. Cook for 1 minute, then cook the other side of the cutlets until golden brown. Remove to a plate and set aside.
Melt the remaining butter and add the mushrooms, garlic and onions to the skillet. Cook, stirring occasionally, until the mushrooms are soft and the onions are tender, about 5 to 7 minutes.
Sprinkle the mixture with the flour and stir, cooking for 1 to 2 minutes. Gradually stir in the chicken broth, then add the salt, pepper and cumin. Bring to a simmer and cook until slightly thickened.
Add the chicken back to the sauce, reduce the heat to low, and cook for 2 or 3 minutes, until the chicken is warmed through. Add the cream until completely combined, bring to a boil, then reduce the heat to low and cook for about 5 minutes. Sprinkle fresh cilantro and serve warm.