Iron skillets are MADE for cornbread.
The seared tuna is a good idea, too.
Get the skillet up to high-medium heat, then turn the heat down (since it will retain the heat, and if you keep it high you'll get LOTS of smoke).
Put the tuna on for about 30-45 seconds per side, slice thinly and serve. Check allrecipes.com for some good sesame rubs and dipping sauces.
For more about care and recipes for your new skillet, go here:
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