Zest and juice the lemons into a blender, add Dijon mustard, anchovy fillets, minced garlic and black pepper. Blend until smooth, then gradually add olive oil.

In a medium skillet, melt the butter over medium heat. Add minced garlic and sauté until fragrant. Stir in panko breadcrumbs and cook until golden brown.

Tear the romaine lettuce into bite-sized pieces and place in a large salad bowl. Drizzle half of the dressing over the lettuce and toss gently.

Sprinkle the garlic butter breadcrumbs over the dressed romaine and drizzle with the remaining dressing, tossing lightly.

Serve the salad on a platter, garnished with freshly grated Parmesan cheese and remaining breadcrumbs.