Preheat the oven to 180° C / 355°F.

Place the potatoes in a pot.

Cover the pot with water.

Add a pinch of sea salt when boiling the water and turn the heat to medium.

Cook for 10-15 minutes until the potatoes are fork-tender.

Stick a small butter square in each muffin hole (or use muffin liners).

Top with a cooked potato.

Smash the potatoes with a small glass.

Add a knob of butter, a sprinkle of sea salt and grated garlic.

Spoon over tomato sauce, add shredded cheddar, crumbled feta, and a sprinkle of za'atar (you can swap for fresh basil instead).

Bake until bubbly and golden (18-20 minutes).

Allow to cool for 5 minutes in the pan.

Use a fork to lift the potato cups out of the muffin tin.

Sprinkle with chopped spring onion or fresh basil.

Serve.