Preheat the oven to 220C, fan-forced. Line an oven tray with baking paper. Quarter the unpeeled potatoes. Put the potato on the lined tray, drizzle with 2 tsp olive oil, season with salt and pepper and toss to coat. Roast for 25-30 mins until golden and tender.
Step 2 — Prep ingredients
While the potato is roasting, thinly slice the onion. Crush or finely chop the garlic. Cut the carrot into 1cm-thick batons.
Step 3 — Prep stock
Crumble 1 stock cube* into a heatproof jug, add 180ml (¾ cup) boiling water and stir to dissolve. Bring a small saucepan of water to the boil for the vegetables.
Step 4 — Cook steaks
PORTERHOUSE STEAK OPTION Heat a medium frypan over high heat until hot (see cooking tip). Drizzle steaks with 2 tsp olive oil, then scatter with 3 tsp pepper and garlic seasoning (reduce for a milder pepper kick). Reduce heat to medium-high and cook steaks, turning regularly, for 4-6 mins for medium-rare, or until cooked to your liking. Remove from pan and cover to keep warm.
Step 5 — Make onion gravy
Meanwhile, melt 10g butter in the same pan over medium-high heat. Cook the onion, stirring, for 2 mins or until softened and golden. Add the garlic and cook, stirring, for 30 secs or until fragrant. Stir in the stock and bring to a simmer. Cook for 5 mins or until reduced. Stir in 1 tsp dijon mustard and 1 tsp balsamic vinegar. Taste, then season with pepper.
Step 6 — Cook vegetables and serve
While the gravy is cooking, cook the carrot in the pan of boiling water for 2 mins. Add the peas and cook for a further 2 mins or until the vegetables are tender. Drain. Divide the steaks and any resting juices, onion gravy, potato and vegetables among plates to serve.