Green bean, potato and tomato salad with a poached egg

If you ever have potatoes and green beans left over from dinner, save them and make this lovely salad for lunch the next day.

 Green bean, potato and tomato salad:

Mixed baby salad leaves
Green beans, cut into bite-sized pieces and boiled for 3.4 minutes
Plum cherry tomatoes, quartered
Potatoes, boiled, peeled and sliced.
Capers
1 egg

Vinaigrette:

Olive oil
Lemon juice
Dijon Mustard
Salt and pepper

Combine salad leaves, green beans and tomatoes in a bowl. Mix a vinaigrette by combining the mustard and lemon, and then slowly adding the oil while stirring constantly. Season the vinaigrette with salt and pepper. Pour the vinaigrette over the vegetables and toss to coat. Arranges the vegetables on a plate, and scatter slices of potato and capers over the top.

To poach the egg, bring water to a boil in a small saucepan. Once it's boiling, reduce the heat so the water is just simmering. Add a few spoonfuls of vinegar to the water. Crack the egg into a small cup, bring the cup close to the surface of the water and gently drop the egg into the simmering water. With a spoon, gently push the egg whites closer to the yoke, to help hold it all together. Let the egg simmer for about 4 minutes. Serve the egg on top of the salad.