Place a 10-inch tube pan in the oven. Preheat oven to 425 degrees F (220 degrees C).
Beat egg whites with salt in a glass or metal bowl until foamy. Add cream of tartar and continue to beat until egg whites stand in peaks. Gradually add honey while beating continually to integrate until stiff peaks form. Lift your beater or whisk straight up: the egg whites will form sharp peaks.
Sift flour and white sugar together. Add 1/3 of the flour mixture into the egg whites and fold gently with a spoon to integrate; repeat in two more additions of the flour mixture to completely incorporate. Stir vanilla into the batter.
Remove hot tube pan from the preheated oven. Pour the batter into the hot pan. Thump pan several times on a flat surface to break air bubbles in batter.
Bake in the preheated oven until golden and the top springs back when lightly pressed, 22 to 25 minutes. Cool cake in pan on a wire pastry rack for at least 2 hours. Run a long, thin metal spatula or knife around edge of pan to loosen cake from pan.
