Start by heating your oven to 350°F. While it's warming up, prepare a 9×5-inch loaf pan with a little baking spray, or shortening( dust with flour). You can also line the pan with parchment paper to make removing the banana bread easier.
Grab a medium-sized bowl and add the flour, baking soda, salt, and cinnamon. Give everything a good whisk so the ingredients blend together nicely. Once you're finished, set the bowl to the side.
In a separate, larger bowl, combine the softened butter and brown sugar. Using an electric mixer, beat the two together for about 2–3 minutes. You're looking for a smooth, fluffy mixture without any large lumps of butter.
Crack the eggs into the butter mixture, adding one at a time. Continue mixing until the eggs blend in completely. Be sure to scrape around the bowl so none of that buttery goodness gets left behind.
Now it's time for the mashed bananas! Add them to the bowl along with the half & half, applesauce and vanilla extract. Mix everything together until the bananas are evenly incorporated. Don't worry if the mixture looks a little lumpy. That's completely fine.
Slowly work the flour mixture into the banana mixture. Use your mixeron its lowest setting, or grab a spatula and stir everything by hand. Either way, stop mixing as soon as you no longer see dry flour. We want a soft, tender banana bread, not a tough one!
Sprinkle the chocolate chips and toffee chips into the batter. Then, using a spatula, gently stir them in. Make sure they're scattered throughout the batter so you get a little chocolate and toffee in every slice.
Transfer the batter into your prepared pan, making sure to spread it evenly. If you'd like, sprinkle a few extra chocolate chips or toffee chips over the top before baking.
Slide the loaf pan into the oven and let the banana bread bake for approximately 60–70 minutes. If you notice the top getting dark before the middle finishes baking, loosely lay a piece of aluminum foil over the pan. Around the 60-minute mark, check the center with a toothpick. A few moist crumbs are perfectly fine, but you shouldn't see any raw batter.
Once your banana bread finishes baking, take it out of the oven and leave it in the pan for about 15–20 minutes. Afterward, carefully remove the loaf and place it on a cooling rack. Let it finish cooling before cutting into those beautiful, chocolate-and-toffee-filled slices.