• Assemble all ingredients and equipment before starting.

Prepare Chicken:

• Slice each chicken breast lengthwise to create thinner cutlets. Season both sides with the chicken bouillon and garlic powder, then let them rest at room temperature for about 15 minutes.
• Heat a skillet over medium-high heat. Add half of the olive oil and half of the butter and let them melt together.
• Sear the chicken in the hot pan about 3 minutes per side, or until each piece is nicely browned and reaches an internal temperature near 160°F, adjusting time for thickness.
• Transfer the seared breasts to a plate and allow them to rest for at least 5 minutes to retain juices.

Sauté Vegetables:

• While the chicken rests, heat the remaining butter and oil in the skillet over medium heat. Add the sliced onions and mushrooms.
• Season the vegetables with a pinch of chicken bouillon and garlic powder. Cook, stirring, until softened and beginning to caramelize, about 2–3 minutes.
• Finish the vegetables with a splash of white wine vinegar, stir to deglaze the pan, then remove from heat.

Assemble and Bake:

• Preheat the oven to 375°F and line a baking sheet with parchment paper or foil. Arrange the rested chicken breasts at least 1 inch apart on the sheet.
• Spoon the sautéed mushrooms and onions evenly over each breast, then top with the shredded Monterey Jack cheese.
• Bake for about 10 minutes, or until the cheese has fully melted and is bubbly. Remove from the oven and let the chicken rest another 5–10 minutes before serving.
• Serve warm with your choice of sides. Enjoy!