Place a medium sized non-stick frying pan over medium heat. Add the olive oil and the onion. Sweat until softened.
Add the vegetables and turkey. Cook for a few minutes until heated through.
Carefully mix to ensure the vegetables are evening distributed in the pan.
Whisk the eggs with the herbs and a little salt and pepper to taste.
Add to the vegetable and turkey mix, ensuring the egg mix is coating all the vegetables.
Cook the frittatta on the stove top until the egg mix starts to set around the edges.
Scatter over the Stilton, then place the frittatta in the oven and cook for 15 minutes or until the egg is set and the top is golden.
Take the frittatta from the oven and leave to sit for 5 minutes, before carefully inverting it onto a plate. Then tip onto another plate so the cheese is on the top.
Either serve immediately or allow to cool before cutting into wedges.