Preheat oven to 375F for convection and 400F for conventional.
Toss the walnuts in oil and salt then place on a baking sheet and toast until golden brown. This will take 20-25 minutes stirring occasionally and rotating the pan once.
While the nuts are cooling slightly, whip the egg whites and sugar until a little foamy but not like a meringue.
Mix the nuts and egg white mixture together and place on a baking sheet with parchment paper or foil and bake for 20-25 minutes until the egg whites dry out stirring occasionally and rotating the pan halfway through.
Remove from oven and cool.