super hot griller here (i grill very hot, but i'm not very hot)
don't overthink things. You don't need a raging fire to grill steak.
Do the "ninja" test. Hold your hand an inch above the grates. If you can hold your hand there for 1 second or less, it's freaking hot.
2 seconds, pretty hot
3 seconds, just hot. Hot enough to sear
4 not very hot, but you can still sear - it just takes longer
5 seconds, not hot
When you're in the 1 or less hot zone, the radiant heat from the coals will likely be more than the temp of the grates. You get a great sear and crust, but you're not going to get great grill marks (if you care)
2 is really the sweet spot. radiant heat has gone down, the grates are hot, you get a nice caramelization
For good marks, make sure your grates or your meat is lightly oiled. LIGHTLY, not dripping.
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want super hot fire?
pour your chimney when the top coals are just starting to get some ash.
Want hotter, longer?
Spread your coals a bit, add a fresh layer of unlit on top. Leave the lid open for 8-10 minutes.
Want thermo nuclear? Do the same, stoke the coals with a blow dryer or an air pump. Be careful though. This will get your kettle 1200+ and things get funky. Charcoal grate will sag, cooking grate will lose its seasoning (and sometimes its outer metallic coating) Porcelain may chip where the welds are. Baby jesus cries and does not recommend getting your grill this hot.
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reverse sear:
- produces a great cook. nice and even throughout.
- timing can be tricky. it takes some practice to pull at the right temp and get the right sear without going over.
- you get less grilled flavor because the meats natural juices aren't producing smoke until the sear stage. this can be circumvented by trimming off some of the beef fat and throwing into the coals once the steaks are cooking indirectly. I prefer to foil the fat and set it on grates, but it can be tricky to make it work right. Toss half an onion on the coals as well and your steaks will get a magical flavor.