Wholegrain spaghetti with leeks and hazelnuts

Ingredients:

• 340 g whole grain spaghetti
• 4 tbsp. l. olive oil
• 3 large leeks, white and light green parts only, thinly sliced
• 2 teaspoons of sugar
• 2 tsp balsamic vinegar (preferably aged)
• 1 small head radicchio, halved and thinly sliced, removing the core
• 170 g soft Italian cheese, such as fontina or taleggio, diced
• 1/4 - 1/3 cup hazelnuts, toasted and chopped

Preparation:

1. Bring a large saucepan of salted water to a boil. Add the spaghetti and cook according to package directions. Meanwhile, heat a large skillet over medium-low heat and add 2 tablespoons of olive oil. Add the leeks to the pan and season with 1 teaspoon each of salt and sugar. Cook, stirring occasionally, until softened, about 10 minutes.
2. Drain the pasta, reserving about 1 cup of the cooking water. Add the pasta and its cooking water to the pan with the leeks. Add the remaining 2 tablespoons of olive oil, 1 teaspoon of sugar, and balsamic vinegar. Increase the heat to medium-high and add the radicchio and cheese. Stir until the cheese melts, 3-5 minutes. Season with salt to taste and sprinkle with hazelnuts.