In a small saucepan on a medium heat, add the butter and 1 tablespoon of extra virgin olive oil. Once the butter has melted, add the garlic and allow to gently cook in the butter for a minute before adding the chilli flakes, freshly ground black pepper and fennel seeds to toast for another minute.
Take it off the heat and add the orange zest followed by the juice and vinegar. Taste for seasoning as it may need more salt depending on your butter brand. Feel free to add more vinegar or orange zest.
Using a small, sharp knife, trim the ends off the French beans. Bring plenty of unsalted water to the boil in a large saucepan, blanch the beans in the water for 4 minutes, then drain into a colander before tipping back into the pot. Pour over the warm butter dressing and give it a good toss before piling onto a plate and grating over the Parmesan.
