SWEET PIQUANTE PEPPER & MANCHEGO FRITTATA

500g pack Waitrose & Partners British Ruby Gem Potatoes, cut into 0.5cm-thick slices • 21⁄2 tbsp olive oil • 2 onions, halved and sliced • 6 medium British Blacktail Free Range Eggs • 100g manchego, cut into 0.5cm cubes • 1⁄2 x 400g jar Peppadew Mild Piquanté Peppers, drained • 400g jar Peppadew Sweet Whole Goldew Peppers, drained • About 180g salad leaves