Set a rack in the middle of the oven and preheat to 400°F/204°C.
Bake the croutons: On a baking sheet, coat 1 cup loosely packed, cubed crusty bread with 1 tablespoon extra-virgin olive oil, salt, and black pepper to taste.Bake for 6 minutes, flipping the croutons in between until they are golden-brown in color. When done, croutons should be crunchy around the edges but still slightly soft in the center. Note: Croutons will continue to cook slightly after removing from the oven, so err on the slightly softer side.
Remove from the baking sheet and transfer to a bowl to cool to room temperature.
Make the dressing: While the croutons cool, prepare the dressing. Mash 1 anchovy filet until it forms a paste with a mortar and pestle. Alternatively, use your knife to create a paste. Tilt your knife at a 30 degree angle and scrape the knife across the anchovy mixture. Next, mince the mixture with your knife for a few seconds, then repeat, scraping with a knife then mincing until it forms a paste.
Transfer paste to a small bowl, and whisk in 1 small garlic clove, finely grated, ¼ teaspoon dijon mustard, 1 tablespoon grated parmigiano-reggiano cheese, and 2 tablespoons full-fat mayonnaise. The dressing should now be a thick paste. Slowly drizzle in 1 tablespoon extra-virgin olive oil and 1 - 2 teaspoons freshly squeezed lemon juice, then season to taste with Salt and black pepper.Note: Too strong or thick? Dilute the mixture with some oil. Too subtle? For additional zinginess, add more garlic or mustard; for additional saltiness, add more salt or anchovy; for additional acidity, add more lemon juice.
Test the dressing: To test if the dressing suits your preferences, dip a piece of escarole into the mixture and taste it. The bite should taste garlicky, with a slight bit of acidity and saltiness. You want it to taste slightly less “zingy” than you want it, because when you eat the salad, you'll be eating many bites, so the punchy flavors and zinginess will build up over time.
Prepare the greens: In a medium salad bowl, toss ½ celery stalk, sliced, 4 cups loosely packed chopped escarole, 1 teaspoon of olive oil, and a pinch of salt and pepper to taste. Note: Remember you'll be adding the caesar dressing later, so err on the side of less salt for now.
Toss the salad: To the greens, add 1 ½ tablespoons shaved parmigiano-reggiano cheese, 1 tablespoon capers, 2 tablespoons finely chopped flat-leaf parsley, 1 cup croutons, and 4 ounces canned tuna packed in oil.Toss with the dressing (to taste), then evenly layer the tuna on top of the salad. Enjoy!
Notes
* You can also use store-bought croutons and Caesar dressing if desired.Canned Tuna: If you're going to splurge on anything, I recommend splurging on a high-quality canned tuna product. I recommend purchasing tuna in olive oil, and I like Tonnino and Ortiz brands. I would avoid Wild Planet as I find it a bit pasty.Storage Instructions:This salad can get a bit soggy, so you'll want to toss it right before serving. That said, you can make the different components in advance:
Leftover dressing can be stored in an airtight container in the fridge for 3-4 days.
Croutons can be stored in an airtight container for up to 2 weeks, but they're usually freshest within the first couple of days. I prefer to freeze them in a Ziploc bag, then reheat them in the oven for 5-10 minutes at 250°F/121°C.
Salad ingredients, like escarole, capers, and cheese can be stored in the fridge for 3-4 days. I just make sure to store them separately. For the escarole, store in a tupperware lined with a paper towel to absorb some of the moisture.