FLOURLESS Chocolate Cake baked at 5300 feet (I live and bake at 1000 feet)

I have a recipe for flourless chocolate cake that consists of melted chocolate with beaten egg yolks folded into beaten egg whites with some sugar. Springform pan. 350 degrees. About 40 minutes.

I want to make this at 5300 feet and cannot find out how to adapt the recipe at all, if that's even necessary.

I understand the cake will rise then collapse (normal for this cake).

The only suggestion someone had was to reduce slightly the amt of sugar - but that was conjecture.

Any hints?