For the hollandaise, melt the butter, skim off the white foam and let the butter cool down. The melted butter should be about 40°C.
Put the egg yolks in a bowl and mix it with a whisk. While stirring constantly, add the warm butter to the egg yolks until you have a thick hollandaise sauce. 
Finally stir in the orange zest, orange juice and STROH Rum. Season with salt and pepper. 
For the asparagus, bring a large pot of salted water to the boil. Cut the asparagus stems generously and peel the asparagus. 
Cook the peeled asparagus with lemon slices and bread for about 10 minutes until it is firm to the bite. Serve with sauce hollandaise.