Preheat oven to 450F.
Trim the asparagus and cover in olive oil. Season well with kosher salt, garlic powder, and black pepper. Roast asparagus until slightly brown and fork tender, roughly 10-15 minutes (depending on how thick your asparagus is). Pro tip: shake the pan halfway through to evenly cook.
In a blender, add in egg yolk, lemon juice, Ale-8, cayenne, kosher salt, and black pepper. Pulse just until combined, roughly 3-4 times.
With the blender on, slowly add in the butter, which should be melted and piping hot. Mix until the sauce is smooth, which takes 15-30 seconds.
Serve on the side (or on top) of roasted asparagus.