Ingredients :

• The potatoes — Choose waxy varieties — Charlotte, Amandine, or Roseval. They hold their shape during cooking without turning into a mushy puree at the bottom of the tart. Floury potatoes (Bintje, Agria) will fall apart and make the filling pasty. Cut them into regular slices of about 3-4 mm — neither too thick nor too thin.
• The shredded cheese — Emmental is the neutral and safe choice. But if you want more flavor, a 12-month Emmental-Comté mix changes everything — the Comté brings a slight nutty note you can really taste in the filling. Grate it yourself if you can: pre-shredded cheese is often too dry and doesn’t melt as well.
• The crème fraîche — Thick, not liquid. Thick 30% fat crème fraîche gives a filling that holds up after baking. Liquid cream makes it too damp — the pastry softens from underneath and you end up with a soggy bottom.
• The garlic — One clove, not two. Sautéed gently in butter, it loses its sharpness and releases a sweet, almost sugary fragrance that disappears into the filling without being consciously identified. Raw, it dominates everything — that’s the classic mistake.