Prepare the chicken and seasonings: Cut the chicken breasts into 1-inch cubes (bites). Toss the chicken with salt, pepper, Italian seasoning, and onion powder. Trim the woody ends off the asparagus.

Sear the chicken: Heat olive oil and 1 tablespoon of butter in a large skillet (cast iron recommended) over medium-high heat. Cook the chicken in batches, ensuring not to overcrowd the pan, until deeply golden brown and cooked through (about 5-7 minutes per batch). Remove the chicken and set aside.

Sauté the garlic and asparagus: Reduce the heat to medium. Add the remaining butter to the skillet. Once melted, add the minced garlic and sauté for 30 seconds until fragrant. Add the trimmed asparagus and cook for 3-5 minutes until tender-crisp.

Form the sauce and combine: Pour in the chicken broth (or wine) and scrape up any browned bits from the bottom of the pan to deglaze. Let the liquid reduce slightly, about 1 minute.

Finish and serve: Return the cooked chicken bites to the skillet. Toss everything gently to coat the chicken and asparagus thoroughly in the rich garlic butter sauce. Stir in the fresh lemon juice and red pepper flakes (if using). Garnish with fresh parsley or basil before serving immediately, ideally with cauliflower rice or mashed cauliflower for a low-carb meal.