Prep the pan: Line an 8x8-inch pan with parchment, leaving overhang for easy lifting.
Soften the dates: If your dates are dry, soak in warm water for 10 minutes, then drain well.
Make the base: In a food processor, pulse oats and nuts until they look like coarse flour. Add dates, 1/2 cup peanut butter, 2 tablespoons maple syrup, vanilla, and salt.
Blend until the mixture clumps and holds when pressed. If crumbly, add 1–2 teaspoons water.
Press and level: Firmly press the base into the lined pan. Use the bottom of a measuring cup to smooth it into an even layer.
Make the chocolate topping: In a small saucepan over low heat, melt coconut oil.
Whisk in cocoa powder and 2–3 tablespoons maple syrup until glossy. Stir in 1/4 cup peanut butter for extra creaminess.
Assemble: Pour the topping over the base, tilting the pan to spread evenly. Tap the pan gently to release air bubbles.
Chill: Refrigerate for 1–2 hours, or until the top is set and firm to the touch.
Finish and slice: Lift the slab out using the parchment.
Sprinkle with a pinch of flaky salt if you like. Cut into 16 squares with a warm, sharp knife.
Serve: Enjoy straight from the fridge for the cleanest slices, or let sit 5 minutes for a softer bite.