Optimum Nutrition 100% Gold Standard, Banana Cream. I got a 16 packet box of ON samples, and Banana was just the first one I tried that didn't taste like ass. 130 calories, 24 g protein, 4 g carbs, 1.5 g fat. And it's packed with whatever aminos.
Annnnddd Nutrabolics Isobolic. It's a whey, casein, and egg albumin blend. 110 calories, 23 g protein, 2 g carbs, 1g fat. Plus aminos, CLA, Flax, Bromelain, and other randomness. It blends better than anything else I've tried.
That's per scoop, but the recommended serving is 2 scoops.