Preheat your oven to 220°C. Fill and boil your kettle.
Pour just enough oil into a baking tray to completely cover the bottom and pop into your oven to heat.
Chop the potatoes lengthways into 1cm slices, then chop into 1cm wide chips (no need to peel).
Pour the boiling water into a large saucepan on high heat with 1/2 tsp salt. Add the potatoes to the boiling water and cook until the edges have softened when you poke them with a knife, 5-6 mins.

Meanwhile, zest and halve the lemon. Finely chop the parsley (stalks and all) and put half in a medium bowl with the lemon zest, breadcrumbs and oil for the breadcrumbs (see ingredients for amount). Season with salt and pepper, mix together then set aside.
Once the potatoes are ready, drain in a colander and pop back into the pan. Season with salt and sprinkle on the flour (see ingredients for amount). Give your pan a shake to fluff up the potatoes.
Take your hot baking tray out of the oven, then carefully transfer your potatoes into it in a single layer, turning in the oil. Roast on the top shelf of your oven until golden, 25-30 mins. Turn halfway through.

While the chips cook, finely chop the capers.
Pop into a small bowl with the remaining parsley and three quarters of the mayo. Mix together, then season to taste with salt, pepper and lemon juice.
Chop any remaining lemon into wedges.

Lay the sea bream, skin-side down, onto a baking tray lined with baking paper. Spread the remaining mayo over the top and sides of the fish.
Spoon on the breadcrumb mixture over the mayo, pressing it down with the spoon. Drizzle with oil, then set aside.
When the chips are halfway through cooking, pop the fish on the middle shelf of the oven to bake until golden, 10-15 mins. IMPORTANT: Wash your hands and equipment after handling raw fish. The fish is cooked when opaque in the middle.

While everything cooks, peel and grate the garlic (or use a garlic press).
When 5 mins of cooking time remain, melt the butter (see ingredients for amount) in a large frying pan on medium-high heat. Add the garlic and peas, then stir-fry for 2-3 mins. Season with salt and pepper, then take off the heat.
Gently crush the peas with the back of a fork, then squeeze in a little lemon juice.

Once the chips are cooked, transfer them to a plate lined with kitchen paper to drain.
When everything else is ready, serve up your ultimate fish and chips with the crushed peas alongside.
Finish with a dollop of tartare sauce for dipping and the lemon wedges for squeezing over. Enjoy!