Crispy potato crust tart with vegan tzatziki, olives and herbs; a gluten‑free, plant‑based Mediterranean dish.
Add the potatoes to a large pot of cold salted water. Bring to a gentle boil and cook for about 20 minutes, until tender when pierced with a fork. Drain and allow to cool completely. Preheat the oven to 200 °C (top grill + convection if available). Lightly brush a tart dish with olive oil (a removable‑base tart tin works well; if using a regular dish, line with parchment paper). Place the cooled potatoes inside and mash them with the bottom of a clean mug, pressing them evenly over the base and up the sides. Generously brush with olive oil. Bake on the top rack of the oven for 30 minutes, until golden. Remove from the oven and carefully take the potato crust out of the tart dish.
Place the pine nuts in an oven‑safe dish and bake for 5 minutes, or until lightly golden.
Grate the cucumber and squeeze out excess water with a clean cloth. In a medium bowl, combine the dairy‑free yogurt, grated cucumber, fresh dill, minced garlic, wholegrain mustard, and lemon juice. Season with salt and pepper.
In a bowl, mix olive oil, harissa paste, maple syrup, finely chopped shallot, finely chopped cherry tomatoes, chopped arugula, and finely chopped kalamata olives.
Spread the tzatziki over the potato base, top with the olive mix, and sprinkle with toasted pine nuts. Slice and serve.