• Preheat the oven to 400F (205C) and set oven rack in the center.  Line a standard muffin pan with 12 tulip style muffin cups or DIY your own. Tip: if you have two muffin pans, use both, leaving every other cup empty. This helps all the muffins rise to their full potential and helps create a nice dome.

Toast the Walnuts:

• Place the walnuts in a pan and set them on the center rack in your just turned on pre-heating oven. They'll toast for 15-18 minutes while the oven is heating (keep an eye on the walnuts since they're especially sensitive to heat and because ovens vary in how fast they pre-heat). Transfer toasted walnuts to a board and rough chop once cooled. Set aside a few tablespoons for sprinkling on top if desired. Chop fine. Set aside.

Make the Batter:

• In a medium mixing bowl, add the flour, salt, baking soda, baking powder, and cinnamon. Whisk the ingredients. Set aside.
• In a large mixing bowl, add the sugar, warm coconut oil, eggs, bananas, and vanilla extract. Whisk until the ingredients come together. Add the sourdough discard and whisk again until no white streaks remain.
• To the wet ingredients, add the dry ingredients all at once. Using a silicone spatula, fold in the dry ingredients and mix until no dry flour patches remain. Fold in the chopped walnuts, holding out the small portion for sprinkling on top. .
• Set batter aside to rest at room temperature for 15 minutes.
• Scoop an overfilled large cookie scoop (#20) or about 1/4 C each with batter and transfer to the muffin liners. Distribute leftover batter evenly among cups. Sprinkle with remaining walnuts if desired.
• Reduce the oven temperature to 375F (190C). Place the muffins in the oven and bake for 25-30 minutes. Use a toothpick to test several muffins starting at 25 minutes. Once the toothpick comes out clean with a few crumbs attached, the muffins are ready.
• Transfer the muffins to a cooling rack and cool completely. Once cool, cover for up to four days at room temperature.

  To Freeze: allow muffins to cool completely. Place individual muffins on a parchment lined sheet pan and freeze. Once frozen, transfer to a lidded container for up to two weeks. Thaw at room temperature.

  To Rewarm: rewarm muffins in a 350F oven for 10-15 minutes.