Bring 2 small saucepans of water to the boil for the eggs and peas. Very thinly slice the onion. Combine 2 tsp white wine vinegar and ½ tsp sugar in a bowl. Add the onion, season with salt and pepper and toss to coat. Set aside to pickle, tossing occasionally, until needed.
Step 2 — Toast bread
Halve the bread rolls through the middle. Toast the bread in a toaster or under a preheated grill until lightly toasted. Spread with 15g butter.
Step 3 — Cook eggs
Cook 2 eggs in a pan of boiling water for 6 mins for soft-boiled, or 8 mins for hard-boiled. Drain, then cool in cold water. Peel and quarter the eggs.
Step 4 — Prep peas
Meanwhile, add the peas to the remaining pan of boiling water, return to the boil and cook for 1 min. Drain and return to the pan. Add half the masala seasoning*, a pinch of chilli flakes, if using, and 10g butter to the peas, then coarsely mash. Season with salt and pepper.
Step 5 — Prep salmon and lemon
Separate the smoked salmon slices, then coarsely tear into pieces. Cut the lemon into wedges.
Step 6 — Get ready to serve
Drain the onion. Divide the toast among plates. Top with the smashed peas, smoked salmon, pickled onion and egg. Scatter with a pinch of chilli flakes*, if desired, and serve with the lemon wedges.