Julia Child did it well
<span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">INGREDIENTS</span>
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<li class="ingredient" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 10px; line-height: inherit; list-style: none; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">2 lb /1 kg starchy potatoes</span></li>
<li class="ingredient" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 10px; line-height: inherit; list-style: none; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">½ clove unpeeled garlic</span></li>
<li class="ingredient" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 10px; line-height: inherit; list-style: none; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">4 tablespoons butter, chopped into small cubes</span></li>
<li class="ingredient" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 10px; line-height: inherit; list-style: none; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">1 teaspoon salt</span></li>
<li class="ingredient" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 10px; line-height: inherit; list-style: none; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">⅛ teaspoon pepper</span></li>
<li class="ingredient" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 10px; line-height: inherit; list-style: none; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">1½ cups grated gruyere cheese (or tasty or cheddar)</span></li>
<li class="ingredient" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 10px; line-height: inherit; list-style: none; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">1½ cups cream</span></li>
<li class="ingredient" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 10px; line-height: inherit; list-style: none; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">2 tsp thyme leaves (optional - but highly recommended)</span></li>
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<span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">INSTRUCTIONS</span>
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<li class="instruction" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 30px; line-height: inherit; list-style: decimal; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">Preheat oven to 350F/180C.</span></li>
<li class="instruction" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 30px; line-height: inherit; list-style: decimal; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">Rub a baking dish or round skillet (square 21 x 21 cm / 8 x 8" or round 23 cm / 9" diameter) with the cut garlic, then smear with 1 tbsp of butter.</span></li>
<li class="instruction" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 30px; line-height: inherit; list-style: decimal; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">Peel the potatoes and slice them ⅛"/3 mm thick. Or use a slicer - makes the job much faster!</span></li>
<li class="instruction" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 30px; line-height: inherit; list-style: decimal; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">Spread ⅓ of the potatoes in the dish, then scatter over ⅓ of the cream, salt, pepper, cheese, thyme and butter.</span></li>
<li class="instruction" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 30px; line-height: inherit; list-style: decimal; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">Repeat for the 2nd and third layer, finishing with the cheese.</span></li>
<li class="instruction" style="box-sizing: border-box; padding: 0px; margin: 0px 0px 0px 30px; line-height: inherit; list-style: decimal; background: 0px 0px;"><span style="font-family: tahoma, arial, helvetica, sans-serif; font-size: 10pt; color: #000000;">Cover with lid or foil, and bake for 1 hour to 1 hr 15 min or until the potatoes are soft (use a knife to test), then remove the foil and bake for a further 10 until the top is bubbly and golden. Rest for 10 minutes before serving.</span></li>
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I use more garlic. It may be sacrilege, but Velveeta works really well in this, too. Cooking times vary wildly. Potatoes need to be starchy, not potato salad-y.