- With the rack in the middle position, preheat the oven to 350°F (180°C). Butter two 6-cup (1.5 litre), 10 x 4-inch (25 x 10 cm) loaf pans and line each with a sheet of parchment paper, letting it hang over two sides.
- In a bowl, combine the bananas and the sour cream. Set aside.
- In another bowl, combine the flour, baking soda and salt. Set aside.
- In a third bowl, beat the eggs, brown sugar and vanilla with an electric mixer until the mixture triples in volume. Add the oil in a thin stream. Stir in the dry ingredients, alternating with the mashed bananas. With a spatula, stir in the chocolate. Spread the batter into the pans.
- Place the banana halves on a plate. Sprinkle with the lemon juice and sugar. Place the banana halves on top of the batter, pushing them in lightly.
- Bake for 45 to 50 minutes or until a toothpick inserted in the centre of the loaf comes out clean. Let cool completely on a wire rack.
If you plan on garnishing the loaf with the banana halves, it is best eaten the same day and will not freeze well.