Line an 8” / 20cm square baking pan with baking parchment.
In a measuring cup or small bowl, combine oat milk and ground flaxseed. Set aside to thicken slightly.
½ cup + 2 tablespoons (150 ml) oat milk, 2 tablespoons ground flaxseed
In a large mixing bowl or stand mixer, combine brown sugar, peanut butter, and melted coconut oil. Beat using a handheld electric mixer or your stand mixer on low until smooth.
1 cup (200 g) dark brown sugar, ¾ cup (180 g) peanut butter, ¼ cup (60 ml) coconut oil
Add in vanilla extract and the oat milk mixture and mix again until combined.
1 teaspoon vanilla extract
Stir in the oat flour, baking powder, and salt until well combined.
1 ¼ cup (150 g) oat flour, 1 teaspoon baking powder, ½ teaspoon sea salt
Mix in the chocolate chips.
½ cup (85 g) vegan chocolate chips
Pour into the lined baking pan and use a spatula to spread the batter into the corners and level the surface.
Bake for 24-27 minutes until lightly browned around the edges and firm in the center.
Cool completely in the pan, and then cut into 16 squares.
Notes
If you like fudgy blondies, stick to the shorter cooking time. For a more cake-like blondie, you can bake them for the longer amount of cooking time.