Flour-Free Peanut Butter Chocolate Chip Cookie Sandwiches with Peanut Butter Cream Filling

INGREDIENTS

1 cup

peanut butter

1 cup

(packed) brown sugar

large egg

1 tsp

baking soda

1 tsp

vanilla extract

to 1½ cups milk chocolate or semi-sweet chocolate chips

1 stick

butter, at room temperature

1/2 cup

creamy peanut butter

1 tsp

ground cinnamon

1 2/3 cups

confectioners' sugar ( I used 1⅓ cups)

Melted chocolate or caramel, (optional)