Dice strawberries to measure 1 cup.
Beat butter until light and blend in the sugar.
Add eggs one t a time until incorporated.
Mix in bananas and vanilla.
Whisk together the dry ingredients. Reserve about 2 T to coat strawberries.
Add the dry ingredients, minus reserved, along with the chia seeds and walnuts.
Toss strawberries with the reserved flour to coat them. Gently fold them into the batter.
Place cupcake liners in pan and fill with about 1 1/2 large scoops of batter.
Place in a preheated 425 degree oven and set the timer for 5 minutes.
When the timer goes off, reduce temperature to 375 degrees and continue to bake for an additional 12 minutes or until golden and toothpick comes out clean. Allow to cool on rack for about 5 minutes before removing from pan.