Preheat oven to 425°; slice any large chopped celery in half, pat dry + mix with 1 tbsp oil + salt/pep; add to a sheet pan + roast 15 minutes; flip chopped celery over + roast 10-15 min more until tender + browned

Heat 1 tbsp oil in skillet over med-high; pat pork dry, season with salt/pep + sear on all sides about 3-4 min; transfer seared meat to a sheet pan + bake 8-10 min until cooked through; rest 5 min then cut into 1-inch slices

Microwave potatoes in bag for 6-7 min; let cool 1-2 min + chop into quarters, season with 1 tbsp oil, salt/pep + fav seasonings

Divide all to plates + drizzle horseradish onto pork