I liked it better before I added the bubbles, so either it is not my kind of a drink or I have a subpar brut... in any case, now I am going to explore more drinks with campari + absinth combination

Dry, herbaceous. A more upscale version of death in the afternoon

This belongs in the same category as the Negroni Spagliato but reveals the generality of the recipe as a template for a large class of variations. Chill equal parts red bitter liqueur, fruit liqueur (pomegranate was great), and maybe a dash of added complexity (e.g., absinthe), strain and fill with the bubbly of your choice (leftover brut was awesome), and garnish with citrus zest. Works (and looks) great in a flute as well as in a coupe.