Start by making the Sauce Vierge. Quarter the cherry tomatoes and add them to a bowl. Set aside.
Gently smash the garlic clove with a knife and add it to a small saucepan, along with the olive oil. Heat the oil over low heat until it’s JUST warmed through and becoming more fluid, about 2-3 minutes. Remove the garlic and pour the warmed oil all over the tomatoes and stir.
Add the lemon juice, basil and chives, and season with salt and pepper. Mix well and set aside at room temperature to let the flavours develop. Remember to give it a stir every now and then.
For the potatoes, start by scrubbing them clean, then place them in a large saucepan with just enough cold, salted water to cover them. Bring to a boil and cook for 20-25 minutes, until the potatoes are fork tender (medium potatoes may need longer). Drain and set aside to steam dry for a few minutes.
Preheat the oven to 200°C.
Pour a couple of tablespoons of the Sauce Vierge oily mixture onto a baking tray and transfer over the potatoes. Gently smash each one using the bottom of a cup, back of a spoon or potato masher - use just enough force to flatten slightly, not to break the potatoes apart completely. Drizzle each potato with more of the Sauce Vierge oil and roast until the edges are golden and crispy-edged.
Remove the potatoes from the oven and crumble the feta all over. Place them back in the oven for 5-10 minutes or until the feta warms through and softens.
Remove from the oven again and immediately top each smashed potato with spoonfuls of Sauce Vierge. Serve them piping hot or warm, with any leftover Sauce Vierge tomatoes.