In a medium-sized mixing bowl, mix butter and sugar until light and fluffy.
Mix in egg and vanilla.
Mix in flour, baking powder, and salt.
Remove half of the dough, roll it into a ball, cover in plastic wrap, and refrigerate.
Mix the freeze dried peas into the remaining dough until fully incorporated. Then, ball up that batter, cover with plastic wrap, and refrigerate.
After 15 minutes, remove all the dough from the refrigerator. Split both dough balls in half and roll the halves out to about 14" x 4".
Place a rolled out green section over a rolled out plain section and trim the edges if necessary to perfectly match up the two dough sheets.
Roll the dough together into a log.
Repeat with the remaining two rolled out dough sheets.
Cover logs and refrigerate for at least an hour.
Preheat oven to 350 F.
Slice logs into 1/4" rounds and place on parchment-lined cookie sheets.
Bake for seven minutes or until they get just a little golden. They will harden more as they cool.
Cool on a cooling rack.