To prepare the vinaigrette, mix the mustard, vinegar and sugar together and slowly whisk in the extra virgin olive oil until the dressing emulsifies. Add a little salt and pepper, taste for seasoning and adjust if necessary.
Roast the hazelnuts at 180C for 6-8 minutes. Remove from the oven and tip into a tea towel, rubbing gently to remove the skins. Once the skins have been removed, roughly chop the nuts and set aside.
Remove the stems from the beans and blanch in plenty of salted boiling water. Once tender, drain and refresh in ice water, then strain and set aside. Slice the fennel bulbs thinly and drizzle with lemon juice as you go to prevent them oxidizing. Cut the apples into quarters, cutting away the core, then slice each quarter into 1-2 pieces, depending on the size of the apple. Toss all of the ingredients together in a large bowl, including the nuts, chives, fennel tops and crumbled goats cheese. Drizzle with a little vinaigrette and serve.