Don’t know an exact recipe but there are lots of recipes that incorporate cauliflower for more fiber and volume, and some that use it exclusively in place of potatoes. You could also try using a milk alternative such as skim or almond milk, or something less fattening than butter such as sour cream or even cottage cheese.
Honestly I just use 2%milk and sour cream with a bit of salt and pepper. But you could use skim milk instead and it would still be decent. I usually go with equal parts 2% milk and low fat sour cream mixed together for about 0.5-1 cup total per pound of potatoes.
1lb potatoes = \~346 calories
1 cup milk & low fat sour cream mix = 60 (2% milk) + 100 (low fat sour cream) = 160 calories
500 calories total
A lb of potatoes is a fair amount to put down in a single serving especially if you have some protein and other veggie as well