A nutritional supplement powder and a method of making the nutritional supplement powder are provided. The nutritional supplement powder includes from 20% by weight to 55% by weight protein, from 20% by weight to 50% by weight fructooligosaccharide powder, and an anti-caking mixture that includes calcium silicate and tricalcium phosphate. A weight ratio of the fructooligosaccharide powder to the anti-caking mixture is from 6:1 to 10:1.