Heat the oven to 425°F/ 210°C full convection.
With a small pairing knife remove the small stem (careful not to go too far or all the leaves will fall off) and then cut in half. Save the brussel leaves that fall off for something later if you want. Make sure the brussel sprouts are very dry.
Peel and cut the banana into small pieces and set aside. Zest and juice ½ the lime into the bowl with the cut bananas. Mix
Set a large cast-iron pan on high heat. Add the peanut oil and wait until it is almost smoking. Add the brussel sprouts all at once and quickly turn them on the flat side. *Be careful whenever adding anything that contains water to hot oil as it may splatter.
Continue to fry the sprouts until nicely golden on the bottom. You may need to add more oil so they fry evenly. Season heavily with salt.
Once the sprouts are nicely coloured put the pan in the oven to continue cooking or alternatively you can roast them on a baking tray like in the picture. Roast for about 5-10 minutes until they are tender.
When they are hot out of the oven add the bananas, lime zest and juice and mix together in a bowl or on the tray. Check the seasoning. Serve and enjoy!