Line an 8×8 baking dish (for thinner fudge) or a 9×5 loaf pan (for thicker fudge) with parchment paper, leaving an overhang on two sides to lift the fudge out when set; press the parchment to fit the pan.

In a medium saucepan, combine 1/2 cup chocolate chips and 1/2 cup coconut oil. Melt over medium-low heat, stirring frequently, until fully melted and smooth.

Remove the saucepan from the heat and whisk in 3/4 cup peanut butter, 1/2 cup cocoa powder, and 1/2 cup pure maple syrup until the mixture is smooth and evenly combined.

Pour the mixture into the prepared pan and spread it evenly with a spatula.

In a small saucepan or microwave-safe bowl, melt 2 tablespoons peanut butter and 1 tablespoon coconut oil together until smooth. If using a microwave, heat in 15–20 second intervals, stirring between intervals.

Drizzle the melted peanut butter mixture over the top of the fudge in a back-and-forth motion. Use the tip of a knife or a toothpick to drag through the drizzle in the opposite direction to create swirls.

Refrigerate the pan for about 2 hours, or until the fudge is firm.

Lift the set fudge from the pan using the parchment overhang and place it on a cutting board. Cut into 20 small squares.

Store the squares in an airtight container in the refrigerator for up to one week.