Ratatouille (Confit Byaldi)

Method

1. Make the piperade by sautéing onion in olive oil for 5 minutes. Add garlic and bell pepper, cook 3 minutes. Add tomatoes, thyme, salt, and pepper. Simmer 10 minutes until thick. Spread in the bottom of a baking dish.

2. Arrange the vegetables by alternating slices of zucchini, yellow squash, eggplant, and tomato in a tight, overlapping pattern on top of the piperade. The slices should stand nearly upright, packed tightly.

3. Drizzle with olive oil, sprinkle with thyme, salt, and pepper. Cover tightly with foil.

   Salt early and throughout the cooking process. Salt added at the beginning penetrates the food; salt added at the end sits on the surface. Both are important, but the foundation matters most.

4. Roast at 275°F for 2 hours covered. Remove foil and roast 30 more minutes uncovered to concentrate.

   Roasting at high heat creates caramelization on the surface while the interior cooks gently. Don't crowd the pan — overcrowding traps steam and prevents browning.

5. Serve warm or at room temperature with fresh basil and flaky salt. This is a showpiece dish — bring it to the table in the baking dish.

   Salt early and throughout the cooking process. Salt added at the beginning penetrates the food; salt added at the end sits on the surface. Both are important, but the foundation matters most.

Equipment

• 9x13 baking dish or oval gratin dish
• Mandoline slicer
• Large skillet Recommended: Joyce Chen 14-Inch Carbon Steel Wok

Chef Notes

• The most important thing: Slice the vegetables uniformly thin — 1/8 inch. A mandoline is essential. The visual pattern of alternating colored slices is the whole point of confit byaldi. Uneven slices ruin the presentation and cook unevenly.
• Choose vegetables of similar diameter so the slices are the same size. Japanese eggplant (narrow) matches zucchini better than globe eggplant.
• The piperade base must be thick — it supports the vegetable slices. If it's watery, the vegetables sink and the dish looks messy.
• Slow-roast at 275°F for 2 hours. The low temperature concentrates the vegetable flavors without browning them. The vegetables should be silky and melting, not charred.
• This is the Thomas Keller version made famous by the Pixar film. Traditional ratatouille is a rustic stew — this is the elegant interpretation.

Common Substitutions

Ingredient	Substitution	Notes
Japanese eggplant	Globe eggplant (halve slices)	Larger diameter — cut slices in half
Yellow squash	More zucchini	Loses the color contrast but works
Confit byaldi style	Traditional ratatouille (chunky stew)	Dice everything, sauté, simmer 30 min — rustic and faster
Mandoline	Very sharp knife	Must be extremely thin and uniform

What You're Practicing

Confit byaldi teaches you precision vegetable cookery — uniform slicing, careful arrangement, and slow roasting to concentrate flavors. The same low-and-slow approach applies to confit garlic, slow-roasted tomatoes, and any vegetable you want to transform from raw to silky. Visit Techniques for more.