Blend the softened mascarpone and creme fraiche in a food processor until smooth. Alternatively, you can mix by hand or use a hand or stand mixer. Transfer to a mixing bowl.
In the mixing bowl with the mascarpone mixture, add in the smoked trout, grated garlic cloves, lemon juice, chives, tarragon, lemon zest and cayenne pepper.
Stir together the ingredients until the become one cohesive mixture like so. Transfer to the serving bowl, cover with plastic wrap and refrigerate until serving time.
Serve it with crostini and watch as this dip quickly disappears and gets rave reviews. You will love this decadent smoked trout dip. Enjoy!