Combine all ingredients in a small bowl and set aside.
In a medium sauté pan over medium heat melt butter. When butter is hot add onions and salt, sauté until softened and slightly caramelized, about 12 minutes. Remove from heat and set aside, allow to cool to room temperature.
In the bowl of a stand mixer stir together water, sugar and yeast. Allow to sit for 10 minutes until foamy. To the yeast mixture add sautéed onion, 1 egg, butter, salt and 2 cups of bread flour. Stir to thoroughly combine. Set mixing bowl on stand mixer fitted with dough hook and knead mixture at low speed adding flour a 1/4 cup at a time. Allow all flour to be absorbed before adding more. Knead until dough pulls away from the sides and bottom of bowl, approximately 8-10 minutes.
Coat a large bowl with oil or non stick spray. Form dough into a ball and place in greased bowl. Cover and allow to rise in a warm and draft free area until doubled in size, approximately 1 hour.
Remove dough and knead 2-3 times to deflate and remove any air. Divide dough into 12 equal portions. They should be approximately 88 grams each. Roll buns into desired shape. I used a kaiser knot so the topping had more crevices to adhere to, however a simple round roll will also work. Place shaped buns onto a parchment lined 18"x13" baking sheet and cover with greased plastic wrap or damp kitchen towel. Allow to rise in a warm draft free area until they have doubled in size, approximately 45-60 minutes.
Preheat oven to 400℉. Whith a fork whisk egg with 1 Tbsp of water. Brush egg wash over the entire top of the buns and sprinkle generously with the Everything Topping mixture. Bake for approximately 23-25 minutes until golden brown and the internal temperature has reached 200℉. Remove from oven and slide buns onto a cooling rack and allow to cool.
85℉ is optimal for proofing if your oven has a proof setting or the ability to be set that low.
Preheat oven to 350℉. In a medium bowl whisk together flours, baking powder, baking soda and salt. Set aside.
In a large bowl whisk together brown sugar and oil. Add ones egg at time, whisking after each. Add cooked whole grain cereal, buttermilk and vanilla, whisk until well mixed.
Add dry ingredients to wet all at once. Whisk until just combined but completely incorporated. Pour mixture into a 9"x5"x3" loaf pan sprayed with non stick spray. Sprinkle poppy seeds and sesame seeds evenly on top. Bake for 50-60 minutes or until a toothpick comes out clean. Allow to cool completely on a wire rack before removing from pan.
Beat butter by hand in a medium bowl until soft and pliable. Add honey and mix to incorporate.
Cut loaf into thick slices and serve with honey butter.
Cook whole grain cereal such as Red River as per package directions. Allow to cool completely and measure out 1/2 cup. I will generally cook a pot, cool, divide, wrap and freeze for use in this loaf and other baked goods.