Pre-heat the oven to 200°C.
Grease and line a baking tray with nonstick baking paper. Combine the pork fillet, breadcrumbs, wholegrain mustard, tomato ketchup and seasoning in a food processor. Pulse until the pork is coarse.
Remove from the processor and shape into 4 even sized patties. Bake for 15-20 minutes until the meat is cooked. Remove and leave to cool for a minute. Place a few rocket leaves on the bottom half of the buns. Top with a patty, then some more rocket leaves on top. Place the top half of the burger in place before serving.
For top tips on protecting you and your family when preparing raw meat and poultry, visit Food Safety in the Home.