Step 1

Add the broccoli and cauliflower to a large baking tray and combine with olive oil, salt and black pepper. Roast in the oven at 200C/400F for 18-20mins, or until lightly charred and slightly softened (will cook properly when baked).

Step 2

Melt the butter in a suitably sized pan over medium heat then add garlic. Fry for a minute, then stir in the flour to form a roux. Gradually pour in the milk, continually whisking as you go to avoid lumps forming.

Step 3

Bring to a gentle bubble, then cut the heat and stir in the gruyere and cheddar. Once melted, stir in the mustard, nutmeg and salt & pepper to taste. Stir in the roasted broccoli/cauliflower.

Step 4

Pour into the baking dish, sprinkle over the rest of the cheddar and pop in the oven at the same temp for 20 mins or until golden/lightly charred and bubbly all around the edges. Allow to rest for a few mins to reform shape and cool down, then sprinkle with finely chopped chives and serve up!