Boil the potatoes

• Put the potatoes in a large pot of cold water and stir in the salt.
• Bring to a boil and cook until fork tender right through, about 25 minutes depending on the size of the potatoes.
• Drain in a colander and leave to steam for 5 minutes.

Preheat the oven

• Preheat the oven to 200 °C / 400 °F.

Season and smash the potatoes

• Tip the potatoes into a large mixing bowl and toss with the olive oil, oregano, salt and black pepper.
• Spread them out on one or two large baking trays lined with baking paper.
• Smash each potato with a large mug or flat measuring cup to an even thickness, keeping them intact.
• Leave to sit for 5 minutes so more steam can escape.

Brush with the leftover oil

• Use a brush to collect the leftover oil and seasoning in the bowl and brush it over the potatoes.
• Add a drizzle more olive oil to the bowl if there is not much left.

Roast until crispy

• Place the potatoes in the oven until deep golden, visibly crispy and just starting to char around the edges.

Cool and top

• Remove from the oven and cool for a few minutes; they crisp up slightly more as they cool.
• Top each potato with a teaspoon of tzatziki, then a sprinkle of feta, a sprinkle of red onion, a couple of olive slices and a few small dill sprigs.
• Finish with a gentle squeeze of lemon juice and a pinch of black pepper.