Rinse iceberg and romaine leaves under cold water. Dry thoroughly using a salad spinner or clean towels. Chop or tear into roughly 1- to 1.5-inch bite-sized pieces. Measure 2 cups of each and place into a large mixing bowl.

Prepare tomato

Wash the Roma tomato, remove the stem, then quarter it lengthwise and slice each quarter into 2–3 bite-sized wedges. Add to the bowl with lettuces.

Prepare cucumber

Wash the cucumber. If desired, peel half the skin for texture contrast. Slice the cucumber lengthwise and then into 1/4-inch half-moons. Add about 1 small cucumber’s worth to the bowl.

Prepare red onion

Peel a small amount of red onion and slice very thinly. Use approximately 2 tablespoons of thin rings or slivers. Separate rings and add to the salad bowl.

Prepare hard-boiled egg

Place 1 large egg in a saucepan and cover with cold water by 1 inch. Bring to a boil over medium-high heat, then cover, remove from heat, and let sit for 10 minutes. Drain and transfer to an ice bath for 5 minutes. Peel, then dice the egg into small cubes and add to the bowl.

Season and toss

Sprinkle the salad with 1 teaspoon salt and 1/4 teaspoon black pepper. Toss gently to combine all components so flavors distribute evenly.

Add croutons

Just before serving, sprinkle 1 ounce of croutons over the top so they stay crisp. If serving later, keep croutons separate and add right before serving.

Dressing

Serve dressing on the side (recommended): place 2 tablespoons of vinaigrette or the dressing of choice in a small ramekin or lightly drizzle over the salad and toss gently to coat. Adjust amount to taste.