Make the Pâté: In the bowl of a food processor, combine the thawed edamame, walnuts, fresh mint leaves, chopped green onion, and salt. Pulse until everything is finely chopped. With the motor running, stream in the lemon juice and 3 tablespoons (45 ml / 1.5 fl oz) of water.
Continue to process until the mixture is completely smooth and creamy. 2. Assemble the Sandwiches: Lay out the 8 slices of whole-grain bread.
Spread a generous layer (about ⅓ cup) of the edamame pâté on 4 of the slices.
Top each with ½ cup of arugula, one sliced roasted red pepper, and a layer of thinly sliced cucumbers.
Place the remaining 4 slices of bread on top to complete the sandwiches.