Slice chicken breasts in half lengthwise (to create 4 thinner pieces) and season with 1 ¼ teaspoon salt, 1 teaspoon pepper, ½ teaspoon garlic powder, ½ teaspoon paprika and 1 teaspoon dried oregano.
In a large skillet, heat olive oil and 2 tablespoons butter over medium-high heat. Cook the chicken for 4-6 minutes per side until golden and cooked through. Remove from the pan and set aside.
Lower the heat to medium and let the pan cool slightly for a minute before adding the remaining butter, this prevents it from browning too quickly and keeps the garlic from burning. Stir in the garlic and sauté for about 30 seconds until fragrant.
Add the broccoli, ½ teaspoon salt, ½ teaspoon pepper, chicken stock, and lemon juice, then cook for 3-4 minutes until the broccoli is tender.
Return the chicken to the pan, spoon the garlic butter over the top, and serve. Garnish with lemon zest and parsley if desired.