For the green pea mayonnaise: In a small pot of boiling water, cook the peas for 3 to 4 minutes or until tender and bright green. Drain and cool under cold running water. Drain well.
In a small food processor, purée the cooled peas with the mint leaves until smooth. Add the mayonnaise. Season with salt and pepper. Mix well. Cover and refrigerate until ready to serve.
For the lobster salad: In a bowl, combine all of the ingredients. Season with salt and pepper. Set aside
Assembly: Cover the outside of the buns with the butter.
In a non-stick skillet over medium-high heat, brown the buns on each side.
On a work surface, place 1 lettuce leaf into each bun. Generously top with the green pea mayonnaise. Divide the lobster salad among the buns. Garnish with mint leaves, if desired. Delicious served with fries.