Heat a pan over very high heat. Rub the pork fillet with olive oil and season with garlic powder, salt and pepper.
Place the pork in the heated pan and brown for a couple of minutes a side. Once golden brown on the outside, place the pork in a preheated oven dish and into the oven at 190C for 15 minutes.
For the mash:
Peel and dice the potatoes, then boil until soft. Drain, add back to the pot, add the butter, milk and garlic. Season with salt and pepper, then mash until smooth.
For the sauce:
Using the pan the pork was seared in, reduce the heat to medium. Add the butter to the pan, then the cherries, balsamic, red wine, and thyme.
Allow to simmer for a couple of minutes, then, using a fork, crush the cherries, leaving a couple of them whole. Add the brown sugar, season with salt and pepper and cook for a further 5 to 10 minutes. Remove the thyme sprigs once sauce has cooked through.
Slice the pork, plate alongside the mash, top with the cherry sauce and garnish with fresh thyme and a fresh cherry or two.