, cut horizontally (ask the bakery to do this for you)
, at room temperature
sweet baby gherkin
, sliced in half lengthwise
COMBINE tuna with zest, herbs, Dijon, mayo, capers and peppers in a medium bowl.
CUT crusts from bread, then, using a rolling pin, flatten each slice of bread. Spread each slice with a little butteron 1 side. Divide tuna salad equally among bread slices and smooth evenly with a knife. Lay 2 gherkin slices, end to end, at the short end of each sandwich, and roll into a short log. Wrap tightly with plastic wrap. Refrigerate at least 1 hour, but best overnight, before slicing and serving.