There are tons of recipes online man, once you get the hang of what ingredients cook at what time and temp you can experiment. Learning to cook well is a skill you grow just like lifting, your weights are going to go up as the quality of your cooking goes up because you're actually going to want to eat whatever you have instead of chicken and broccoli for the 1000th time.
My personal favorite is pulled pork, when pork shoulder is on sale near me its $1.50/lb, usually chicken breast runs $2/lb for comparison. So a pork shoulder, chop an onion or two and throw it in, dice a small amount of garlic and pour in a half cup apple cider vinegar and half cup BBQ sauce. Prepare that shit before you go to bed, cook on low 8-10 hours, and wake up to your shithole smelling like a Texas BBQ Pit. All those ingredients besides the pork are fairly shelf stable, you can buy a small bag of onions for instance and use them all before they go bad, even for a single guy