Bulk shake? 16oz whole milk is 300 cals, 2 scoops protein is anywhere from 150-250 cals, peanut butter can be 200-400 cals. At minimum that’s 650 cals. Drink in the AM and post workout and it’s easily 12-1400 cals. Cheaper and so much better than that filler-filled “mass gainer”
It’s really easy to make a bulk shake with just milk, peanut butter, and whey. Throw in a banana, strawberries, and/or blueberries to get some real flavor.
Also, tablespoon extra virgin olive oil. Great fats and omegas. Also an easy 100 cals that you’ll never taste in your shake. Disclaimer - it will leave an oily film in your shaker cup.