Just putting in a strainer and rinsing under hot water. The grease runs right out. It is dry as crap....but you can add tomato sauce...etc. It is what I lived on when I was in my 20's and poor.
You can also poach meats and skim the fat off by fully submerging in water. Stew beef works great for this. Just make a good soup and skim fat off top after it is cooked down. I have an electric pressure cooker and you can break down stuff very nice in 45min. Same as slow cooking for 5+ hours. I like making barley beef soup like this.
But...truth be told, not much is cheaper than boneless skinless chicken breast. (other than whey which I will show later) Around here chicken it can be found any day at 1.99/lb. No need to skim and fat . Chicken is about 6g of protein / oz (uncooked). That is about .02/gram protein.
Whey, I buy 15lb of unflavored isolate 90% for $155. So that is 240oz @ 90% protein is 216oz. (or 6123g of total protein) @ $115 = $.018/gram (so a little cheaper than even boneless skinless).
Even if you go with a good protein like ON100%. From memory it is 72 servings of 24 grams. So 1728 total g protein. You can usually pick them up for about $55. That is about $.03/ gram of protein )or just a little more than chicken breast).
I get about 1/3 my daily protein of 230g +/- from whey. To get the balance, I eat about 1lb of lean meat a day and the rest is dairy. (I love milk). Eating a high protein diet is expensive. Take my 230g/day habit. If I got it all from a cheap protein source like chicken breast, it costs me about $1700/year just to meet my protein needs.
If I got it from lean beef, (which is about $.05/gram) it would run me $4400/year just in beef.
I have eaten like this for the last 8 years. When I hear guys say they eat 300g/day, frankly I think they are full of crap. It takes me a lot to get the 200+ in daily and if I did not use whey, I am not sure I could do it consistently.
If you wanna go super cheap. Get a case of Ramen ( $5-7 ) and go fishing. I lived on Channel Cats and Sunnies when I was a runaway in my teens. All you need is rod & reel, turn over a dead tree for bait. High Protein and Omega 3s and the Toxic Waste from the Schuylkill river was good for the gains.
Half a cow in freezer from local farmer $600-900. Depends on live or hang weight and butcher cost Deer meat in other freezer -free Turkey -free And those broccoli frozen bags for 79 cents I eat 2 a day Fish by the trap load -free 25lb bag of rice $15 Tiger sauce-4 And whatever else we are growing on the farm