Preheat oven to 400°F.
In a bowl combine the parmesan and breadcrumbs.
Toss the cauliflower with the olive oil and 2 tbsp cider.
Add the parmesan-breadcrumb and season with salt and pepper.
Place the cauliflower onto a parchment line sheet pan.
Any leftover breadcrumb sprinkle over the cauliflower.
Place into oven and roast for 25-30 minutes until the cauliflower is tender and the parmesan-crumb is golden brown.
Remove from the oven, place onto a platter.
Combine ¼ tsp cider and cider vinegar.
Sprinkle cider-vinegar across the cauliflower and garnish with the sliced chives.