Instructions

• Prepare the slow cooker: use a 6‑quart slow cooker (do not use a smaller one or it may overflow). Line it with a slow-cooker liner if you like for easy cleanup, then spray the liner (or the base and sides of the pot if not using a liner) with cooking spray. Set the pot aside.
• In a large bowl, whisk together 2 large eggs, ½ cup canola or vegetable oil, ½ cup packed light brown sugar, ¼ cup granulated sugar, and 2 teaspoons vanilla extract until combined.
• Add 1 ½ cups mashed ripe bananas (about 3 large bananas) to the bowl and stir to combine.
• Add 2 cups all-purpose flour, 1 teaspoon baking powder, ½ teaspoon baking soda, ¼ teaspoon salt (or to taste), and 1 teaspoon cinnamon (optional). Stir just until the dry ingredients are incorporated and there are no large streaks of flour.
• Turn the batter into the prepared slow cooker and spread it into a smooth, even, flat layer.
• Wipe the mixing bowl clean (or use a second bowl). Add the remaining ½ cup packed light brown sugar and 1 ½ cups boiling water to the bowl and whisk until the sugar is dissolved.
• Carefully pour the hot brown sugar–water mixture evenly over the batter in the slow cooker. Do not stir—the liquid will form the brown sugar sauce as the cake cooks.
• Cover and cook on HIGH for about 1½ to 2 hours, or until the edges are set and light golden brown and a toothpick inserted into the center of the bread comes out clean. Start checking at just over 1 hour to avoid overbaking; slow cooker times vary. (This recipe has not been tested on the LOW setting.)
• When the cake is done, use oven mitts to remove the ceramic insert from the base. Allow the cake to cool in the insert for about 10 minutes to settle the sauce, then serve.