Line an 8x8 baking dish with parchment paper and set aside.
Toast the oats, coconut, sesame seeds, pepitas, and sunflower kernels in a skillet over medium heat, stirring frequently until golden. While that's toasting, heat the honey and peanut butter in a small saucepan, cooking until the peanut butter has melted and the mixture is bubbling.
Transfer the toasted dry ingredients to a large bowl and add the ground flaxseed and chocolate chips.
Pour the hot mixture over the dry ingredients, and stir until all the chocolate has melted and the ingredients are coated in the honey-peanut butter mixture.
Pour the granola bar mixture into the prepared baking dish and firmly pack it down with a spoon or spatula. Place it in the fridge until cool. Cut in half once, then cut the other way 3-4 times, until you have 8-10 bars.
