In a pan set over a medium heat, add the oil and half of the butter, and allow the butter to melt.
Season the chicken breasts with salt and pepper, and brown them on both sides - it can take up to 10-12 minutes.
Remove the chicken breasts from the pan and set aside.
Add the remaining butter, and leave it to melt.
Add the flour, and whisk well to get a smooth paste, then pour in the stock, and continue to whisk until the gravy thickens.
Add the garlic granules and whisk well.
Return the chicken breasts to the pan, and place a lid on.
Leave it to cook for a further 10-15 minutes until the chicken breasts are cooked through - turn them onto the other side now and then to avoid them from sticking to the pan.
Add the herbs, check if the gravy needs any more seasoning, and remove the pan from the heat.
Serve with mashed potatoes and greens.