Bring a large saucepan of salted water to the boil and cook the penne according to the package instructions.
Heat 1 tbsp oil in a large frying pan, then add the bacon, stirring occasionally until golden and crisp. Pour off any excess rendered bacon fat to a small bowl (keep it to cook the zucchini!) then transfer the bacon to a plate lined with paper towel to absorb any excess grease. If needed, deglaze the pan with the chicken stock.
Return the pan to the heat with the reserved bacon fat and the remaining olive oil. Add the zucchini and cook until softened and golden-brown. Remove to a plate lined with paper towels.
Return the pan to the heat, then add the garlic and cook for 1 minute, or until fragrant. Add the drained pasta, bacon, zucchini, sour cream and chicken stock powder to the pan. Toss gently to combine, until the stock powder dissolves, then season to taste with salt and pepper.
Divide the zucchini and bacon pasta between plates, top with Parmesan cheese and serve.
