Which charcoal to use, and which to avoid

Short cooks over direct heat need a fire that is hot within a reasonable time, even across the length of the bed, and stable for the twenty or thirty minutes you are actually cooking. You are not looking for a fuel that burns for six hours. You are looking for one that gets properly hot and stays even.

Lump hardwood charcoal

Irregular chunks of carbonised hardwood. Lights faster than briquettes, burns hotter, and gives the cleanest flavour. The pieces are uneven, so the bed is less uniform and you may need to level it with tongs. This is the default choice for skewer cooking and the one worth starting with.

Briquettes and heat beads

Compressed and uniform, so they build a flat even bed and hold a steady temperature for longer than lump. They take longer to come up to heat and some brands include binders that give off a smell early in the burn. Let them ash over fully before cooking and that disappears. A good choice for long sessions and for the enclosed F2 body.

Mallee root

An Australian favourite, dense and long burning with a distinct flavour. Excellent fuel, though it is slower to establish than lump charcoal, which makes it better suited to a longer session than a quick tray of arrosticini.

Coconut shell charcoal

Dense, low smoke, low ash, and a long steady burn for its size. Common in Middle Eastern cooking for exactly this reason. Well suited to kebabs and worth trying if you cook that way often.

• Self-lighting or instant-light briquettes. They are impregnated with accelerant. It burns off, but not always before your food goes on, and it can taint a short cook badly. On a three minute arrosticini cook there is no burn-off window at all.
• Petrol, methylated spirits or any flammable liquid as a starter. Dangerous, and it flavours the food. Use a chimney starter or a firelighter.
• Treated, painted or manufactured timber. Never. It releases genuinely toxic compounds. This includes offcuts of treated pine, old pallets of unknown origin, chipboard and anything with adhesive in it.
• Cooking over flame. Not a fuel problem but the most common one. Wait until the coals are covered in grey ash with red underneath. Flame deposits soot and scorches the outside before the middle moves.

More than you think for a short cook, and less than you think for a long one.

A skewer grill wants a bed deep enough to hold its heat while the food is on, because small skewers going onto a thin bed will pull the temperature down immediately. Bank it under where the meat will sit rather than spreading it thin across the whole tray, and use the height adjustment for fine control rather than adding and removing fuel mid cook.