Chill the lettuce: Wash and spin-dry romaine well. Lay the leaves on a towel, then refrigerate for at least 30 minutes. Cold lettuce is key to that steakhouse crunch.
Make the croutons: Heat oven to 375°F (190°C).
Toss torn bread with 3 tablespoons olive oil, a pinch of salt, and a few grinds of pepper. Spread on a sheet pan and bake 10–14 minutes, tossing once, until golden and crisp at the edges. Cool completely.
Build the dressing base: In a large bowl, combine garlic, anchovies, Dijon, Worcestershire, lemon juice, and the egg yolk (or mayonnaise).
Whisk until smooth.
Emulsify: Whisking constantly, drizzle in 1/3 cup neutral oil in a slow, steady stream until thick and glossy. Whisk in 2–3 tablespoons olive oil for flavor. The dressing should be creamy and pourable.
Taste and adjust with salt, pepper, and more lemon if needed.
Prep the cheese: Use a vegetable peeler to shave wide ribbons of Parmesan. Set aside a big handful for the top.
Toss like a pro: Add the romaine to the bowl with the dressing. Start with less dressing than you think you need.
Toss by hand to coat every leaf, adding more dressing as needed. You want a light, even sheen, not soup.
Finish with crunch and salt: Fold in croutons and most of the Parmesan. Toss again.
Top with remaining cheese and a shower of black pepper.
Optional steakhouse upgrades: Add warm, crisped pancetta, or lay thin slices of grilled steak or roast chicken over the top. A final squeeze of lemon wakes everything up.
Serve immediately: Caesar shines when the lettuce is cold, the croutons are crisp, and the dressing is freshly clinging to the leaves.