1. Season the chicken on both sides with salt and pepper. Heat a little oil in a skillet over medium-high heat and sear the chicken until golden on both sides and cooked through to an internal temperature of 165°F. Transfer the chicken to a plate and keep it warm.

2. Reduce the heat to medium and, in the same skillet, melt 2 tablespoon of butter. Add the minced garlic and cook for about 1 minute, until fragrant but not browned.

3. Sprinkle the flour over the garlic and stir to form a paste. Cook for 1-2 minutes, stirring constantly. Gradually whisk in the chicken broth, smoothing out any lumps, and simmer until the gravy has thickened. Stir in the heavy cream (if using) and season with salt and pepper to taste. Let the gravy simmer gently while you prepare the potatoes.

4. In a large pot, boil the cubed Yukon Gold potatoes in salted water until fork-tender, about 12-15 minutes. Drain the potatoes well.

5. Mash the hot potatoes with 2 tablespoon of butter and the warm milk until smooth and creamy. Stir in the shredded cheddar cheese until melted. Season with salt and pepper to taste.

6. Slice the seared chicken if desired. Spoon a generous mound of the cheesy mashed potatoes onto each plate, top with the chicken, and ladle the warm garlic gravy over everything. Garnish with chopped parsley or chives for a beautiful and flavorful presentation.