I made the most fabulous scalloped potatoes - the only good thing I got out of my first marriage - other than my freedom - and of COURSE I forgot to take pictures. But here is what passes for a recipe:

1 clove garlic, split lengthwise
4 very large russet potatoes
2 to 3 cups cream
2 to 3 tablespoons butter
additional milk just in case

You will need a mandoline ...

(fancy French slicing machine) or the thinnest slicing blade on your Cuisinart.

Hand slicing yields so-so results. You will also need a big heat-proof pan. I use a copper dutch oven, but if it's a fancy dinner I use a yellow Le Creuset pan. Oh wait - I have pictures of these!

Preheat oven to 350, or 375 if you're in a hurry.

Peel one potato - I peel them as I need them for slicing so they do not discolor, and as you will need all the starch don't submerge them in water.

Using your mandoline slice the potato about 1/8 inch or slightly thinner. Rub the inside of your Dutch oven with the cut side of the garlic, then throw the garlic away.

Fan the potato slices in the pan, working from the outside in, and making concentric circles. (look it up)
Fill the center with the little bits from the end of the potato, then dot butter over the slices and pour on some cream - you want the cream to just cover the slices when you press down.

Peel and slice another potato, fan as above, dot with butter and pour on the cream. Repeat until you're done with the potatoes and the cream - if you run out of cream use some milk. Be sure when you're done that the potatoes are submerged when pressed.

If you are a cheese hound you can sprinkle on some gruyere, parmigiano (only the real Reggiano stuff no cheap imitations allowed!) Sprinkle with salt and place pan on stove over medium-high heat. Bring to a simmer, then smack the pan in the oven and bake until potatoes are easily pierced with a paring knife. This usually takes about an hour. If the potatoes are getting too brown, cover them, then remove the cover to crisp them for the last 10 minutes or so.

Let rest about 10 minutes, then eat.  You can use more potatoes and more cream to serve more people - I figure about a potato per person but my friends tend to be big eaters.

As you become more comfortable with this recipe you can layer in some cheese. use half potato and half fennel, use some celery root in place of some of the potatoes...I'm sure you will find lots of variations. Maybe even some broccoli. Perish the thought.