Run a knife along the outside parameter of the avocado, starting and ending at the stem. Twist to separate the two halves. Squeeze both halves like you’re juicing a lemon to extract the fruit into a bowl. Discard the pit.
Pour the lemon juice on top and smash it into the avocado with a fork. Do the same with the salsa, salt, and cheese and mix until well combined. Serve immediately.