Preheat oven 350°

Boil whole potatoes (skin on) until fork can be inserted.

Fry bacon until crispy and then crumble.

Dice onion and saute in butter until transparent.

Shred block of cheese.

In large bowl mix sour cream and mayo together.

Add the cooked onion and crumbled bacon. (I reserved some bacon for the top)

Fold potatoes into sour cream/mayo mixture.

Make layers beginning with potatoes then cheese. I made 2 layers. Top with cheese and bacon.

Bake at 350° uncovered for 1 hour.