Step 1

Let 1 teaspoon unsalted butter sit at room temperature until softened.

Step 2

Peel 1 large hard-boiled egg. Peel 1/2 medium avocado and thinly slice lengthwise.

Step 3

Spread the butter evenly on 1 sheet matzo. Arrange the avocado slices evenly on the matzo. Squeeze the juice from 1/2 medium lemon over the avocado, then sprinkle with 1/2 teaspoon of the kosher salt.

Step 4

Grate the egg directly onto the avocado with a Microplane or on the smaller holes of a box grater. Season with remaining 1/4 teaspoon kosher salt and 1/4 teaspoon red pepper flakes.