Preheat the oven to 200°C (fan) / 400°F / Gas Mark 6.
Peel the celeriac (you can do this with a potato peeler or small sharp knife). Trim off the ends and slice the celeriac into 4 rounds. Score shallow lines on both sides of each 'steak' in a cross hatch as pictured above.
In a small bowl mix the oil, mustard, maple syrup, garlic and soy sauce. Season well with salt and black pepper.
Line a baking tray with greaseproof paper / baking parchment. Brush each piece of celeriac generously on both sides with the marinade. and place on the baking tray. Bake for 25 minutes.
Remove the steaks from the oven, flip over and brush with the remaining marinade. Return to the oven for a further 15-20 minutes until deeply golden brown and cooked through.
Serve with mashed potato or butter bean mash and vegan gravy.
