A question about a recipe: Summer Squash Gratin with Salsa Verde and Gruyere

Yes, you can leave it out, but why would you?I f you are allergic to them, that is one thing, but anchovies contribute an element of taste, umami, to the dish that makes it particularly savory. You might not like to chow down on an anchovy alone, but combined with other foods, it adds elusive flavor that you will not pick out as 'anchovy'.

Sure -- you can leave it out.