Preheat your oven to 180°C (350°F). Line a muffin tin with paper liners or lightly grease it.
In a large bowl, whisk together the whole wheat flour, sugar, and baking powder. This creates a uniform dry mixture to combine with the wet ingredients.
In a separate bowl, stir the peanut butter, milk, eggs, and honey until the mixture is smooth and slightly frothy, with a fragrant nutty aroma filling the air.
Pour the wet mixture into the dry ingredients and gently fold everything together using a spatula or whisk, just until combined. Be careful not to overmix; the batter should be slightly lumpy but well incorporated.
Spoon the batter into the prepared muffin tin, filling each cup about three-quarters full. The batter should look slightly thick but scoopable, with a matte finish.
Bake in the preheated oven for 15-17 minutes, or until the muffins turn golden on top and a toothpick inserted in the center comes out clean with no wet batter clinging.
Remove the muffins from the oven, and let them cool in the tin for about 5 minutes. Then transfer them to a wire rack to cool completely or enjoy warm while the centers are still sticky and gooey.
Once cooled slightly, enjoy these moist, nutty muffins with crusty edges and tender centers—perfect for snacking or breakfast.