1. Prepare all ingredients by mincing garlic, chopping herbs, and slicing mushrooms.
2. Heat a large skillet over medium heat and add half the butter and olive oil. Sauté mushrooms seasoned with 1/2 teaspoon garlic salt until golden brown, about 5 minutes. Remove mushrooms and set aside.
3. Season chicken with 1 teaspoon garlic salt and pepper. In the same pan, add remaining butter and olive oil, then cook chicken in a single layer for about 2-5 minutes per side, depending on thickness, until cooked through. Remove chicken and keep warm.
4. Add minced garlic to the pan and sauté for 1 minute until fragrant. Stir in chopped fresh dill, parsley, green onions, and other herbs like thyme, sage, and rosemary; cook for another minute.
5. Pour in chicken broth and heavy cream (or coconut milk) and bring to a light simmer. Return mushrooms to the pan. If needed, stir in the arrowroot slurry to thicken the sauce, cooking briefly until it thickens.
6. Return the chicken to the pan, coating it in the sauce. Adjust seasoning with additional garlic salt, salt, and pepper as desired.
7. Serve immediately over your choice of side such as mashed potatoes, rice, roasted potatoes, or cauliflower rice.