Wash the potato and pat dry. Prick with fork 4-5 times on both sides. Place on a microwave safe plate and microwave on HIGH for 5 minutes. Use oven mitts to flip the potato and microwave an additional 3 minutes. Remove from microwave and set aside.
While the potato is cooking, mix together the ricotta and pesto in a bowl.
When potato has cooled enough, split open the potato and stuff in the baby spinach leaves. Top with the ricotta-pesto mixture, and enjoy.