In a mixing bowl, combine all the spice ingredients and mix well.
Add the softened Kerrygold butter to the spice mix and incorporate it into the butter.
Divide the flavoured butter into two. One half can be wrapped in plastic wrap and kept in the fridge to use throughout the week. Keep the other half for the cauliflower.
Once the cauliflower head has been cut and prepped, arrange them in an oven safe dish. Massage the flavoured jerk butter into the cauliflower.
Roast in an oven at 190 degrees Celsius for 15 minutes. Remove and baste the cauliflower with more spiced butter. Place back in the oven for another 15 minutes.
Once the cauliflower has roasted for 30 minutes, remove from oven and give them a turn. Add more flavoured butter if needed. Turn up the heat to 200 degrees Celsius and roast the cauliflower for a final 10 minutes.
Prep the watermelon salad by slicing the watermelon in slices. Mix the finely chopped red onion with the mint. Set aside.
Remove the cauliflower from the oven and sprinkle with lime zest before serving it with the watermelon, and onion and herb salsa. Serve immediately and enjoy.