Prep the pan and oven: Heat oven to 350°F (175°C). Line a 9x5-inch loaf pan with parchment, leaving overhang for easy lifting. Lightly grease the sides.

Mash the bananas: In a large bowl, mash bananas until mostly smooth with a few small lumps for texture.

Whisk in the wet ingredients: Add granulated sugar, brown sugar, melted butter, eggs, and vanilla. Whisk until combined and glossy.

Mix the dry ingredients: In a separate bowl, whisk flour, baking soda, baking powder, salt, and cinnamon.

Combine gently: Add dry ingredients to wet. Stir with a spatula just until the flour disappears. Do not overmix or the loaf will be dense.

Prep the add-ins: Toss the diced strawberries with 1 tablespoon flour to reduce bleeding and sinking. Fold in strawberries and chocolate chips, reserving a few chips for the top.

Fill the pan: Scrape batter into the prepared pan. Smooth the top. Sprinkle with reserved chips and a light dusting of coarse sugar if using.

Bake: Bake 55–70 minutes, depending on your oven. Start checking at 55 minutes. A tester should come out mostly clean with a few moist crumbs (melted chocolate may smear).

Cool properly: Let the loaf cool in the pan 15 minutes, then lift out to a rack. Cool at least 1 hour before slicing so it sets and doesn’t crumble.

Serve: Slice thickly. Enjoy warm or room temp. It’s great plain, with butter, or a swipe of strawberry jam for extra fruitiness.