In a bowl combine peanut butter, egg, sugar and oats. Mix will. Chill in the refrigerator for 2-3 hours
Preheat oven to 350 degress
Line a baking sheet with parchment paper.
Using a small scooper, scoop dough out into small balls (about 1 inch balls). Using a fork, press down evenly on cookie creating "fork marks".
Bake for 10-12 minutes
Transfer cookies to a drying rack and allow to cool
Meanwhile, place chocolate chips in a glass bowl and microwave on low for about 15-20 seconds. Remove bowl and stir chocolate. Place bowl back in microwave and repeat for another 15-20 seconds. Continue until chocolate is fully melted (don't overheat/burn chocolate). Using a small spoon, drizzle chocolate over peanut butter cookies.