Preheat the oven to 375°F (190°C). Cut the day-old bread into 1/2-inch (1.2 cm) cubes so you have about 6 cups. Spread the cubes in a single layer on a rimmed baking sheet.

Make herb oil

In a small saucepan or microwave-safe bowl, combine 6 tbsp extra-virgin olive oil, 2 tbsp unsalted butter, 3 minced garlic cloves, 3 tbsp chopped parsley, 1 tbsp chopped thyme, and 1 tsp dried oregano. Warm gently over low heat for 1–2 minutes just to bloom the herbs and soften garlic; do not fry or brown the garlic.

Toss and bake

Pour the warm herb oil over the bread cubes and toss thoroughly to coat. Spread cubes back on the baking sheet in a single layer. Season with 3 tsp fine sea salt and 1 tsp freshly ground black pepper. Bake for 12–18 minutes, tossing once halfway through, until golden-brown and crisp. Remove and cool on a rack.

Caesar Dressing

Combine aromatics

In a medium bowl, mash the 4 anchovy fillets with 1 grated garlic clove and 1 tsp Dijon mustard to form a smooth paste.

Emulsify

Whisk in 2 egg yolks, 3 tbsp fresh lemon juice, and 1 tsp Worcestershire sauce until combined. Very slowly start drizzling in 3 tbsp extra-virgin olive oil and then the 6 tbsp neutral oil in a thin steady stream while whisking vigorously to create an emulsion. If mixture becomes too thick, whisk in 1–2 tsp warm water to loosen.

Finish dressing

Fold in 1 cup freshly grated Parmesan. Season to taste with 1 tsp fine sea salt and 1/2 tsp freshly ground black pepper. Taste and adjust lemon, salt, or anchovy if needed. Refrigerate up to 2 days; bring to room temperature and whisk again before using.

Salad Assembly

Prepare lettuce

Trim the stem ends of the baby romaine hearts, separating them into whole hearts or large leaves as preferred. Rinse under cold water, spin dry in a salad spinner or pat dry thoroughly with clean kitchen towels to remove excess moisture.

Toss salad

Place the dry baby romaine in a large mixing bowl. Add about 3/4 of the cooled herb croutons (reserve the rest for garnish). Add approximately 1 1/2 cups of the grated Parmesan to the bowl (reserve remaining Parmesan for serving). Drizzle 3–4 tablespoons of the Caesar dressing over the greens and toss gently but quickly to coat—add more dressing, 1 tablespoon at a time, until leaves are lightly but evenly coated. Taste and season with coarse sea salt and freshly ground black pepper if desired.

Serve

Transfer tossed salad to a serving platter or divide among plates. Sprinkle remaining Parmesan and reserved croutons on top. Serve immediately with lemon wedges on the side for guests who want extra brightness.