In a mixing bowl add chicken, lemon juice, salt and pepper. Rub the spice to coat chicken evenly
Heat oil in an iron skillet on medium heat. Add chicken and cook it for 5 min. Then flip it over and cook for another 5 min. Once done remove chicken from the pan and put aside.
In the same pan add sliced mushrooms, minced garlic, salt and pepper to taste. Stir it for 2-3 min. Then add onions, tomato, cayenne pepper and paprika and, cook further for 6-7 min. Once done turn off the heat and return chicken to the pan. Garnish with parsley.
Meanwhile cook polenta in a separate pan according to package instructions.
Serve sautéed mushroom and chicken on the bed of creamy polenta.