Mound the ingredients in hollowed-out bread, aiming for lots of flavor and variety. Cilantro Pepita Pesto makes this packable picnic sandwich distinctive! Plan on 3 or 4 inches per person.
With the motor of the food processor running, mince the garlic by dropping it through the feed tube. Process until it is very fine and has flown onto the processor bowl. Add the cilantro, pepitas and salt. Process for about 10 seconds, stopping to move things around if they get hung up. With the machine running, pour oil through the feed tube in a thin stream, processing until everything is well blended. Pour in the lime juice.
To assemble the pan bagnat:
Slice the baguette crosswise a third of the way down from the top. With your fingers, make it hollow by tearing out the softer bready insides.
Spread both top and bottom hollows very generously with pesto.
Slice the baguette crosswise a third of the way down from the top. With your fingers, make it hollow by tearing out the softer bready insides. Spread both top and bottom hollows very generously with pesto. In the bottom, mound in the options, aiming for lots of flavor and variety. Sprinkle with salt and freshly ground pepper and a bit of red wine vinegar.
Place the other half of the baguette on top—it should fit over your layers without too much of a gap. Wrap tightly in plastic wrap and then fasten with rubber bands, at intervals, to press the sandwich together. Pack in your picnic basket, along with a small cutting surface and a good serrated knife.
To serve, slice the Pan Bagnat right through the plastic. Peel away the plastic as you eat the sandwich.
Notes
Pepita is the Spanish word for pumpkin seeds.
If you don’t have enough cilantro, supplement with parsley.