First generation cross will show the dominant traits, but each bird will have a copy of the recessive traits as well. So, in hte first generation you will have a lot of birds that look like a sizzle.
BUT
Second generation cross of these youngsters will give results ALL OVER THE PLACE. Very few will have ALL sizzle features. This is because you will have recessives pairing up, but not all on hte same bird. One bird my end up with 4 toes, another with silkie feathering, another without black skin, another without a crest, etc. This is the generation where you need to do the most culling from your breeding pen, keeping only birds that have as many as possible of the traits you want to perpetuate, and as few undesirable traits as possible.
This is why getting sizzles that are farther along in the generations will give you much better quality of sizzles.
Black skin, crest, muffs/beards, multiple toes and frizzling are dominant traits; some of these are incompletely dominant. Silkie feathering is recessive; it is not part of the sizzle phenotype.