Combine the milk and cream, add the banana bread and soak for an hour in the fridge.
Slice and add the bananas to the cream mixture. Blend or emulsify the mixture until smooth (no solid trace of bread or bananas).
Add cream mixture to a pot and bring to a low simmer.
While the cream simmers; whisk egg yolks with sugar, spices and vanilla until smooth (2 min).
Slowly add 1/2 a cup of the hot cream while whisking briskly. Continue to add 1/2 cups at a time slowly and patiently until more than half of the cream has been combined. Transfer the egg custard to the remaining cream in the pot and simmer until custard is thick enough to coat the back of a spoon. Always whisking! (strain the mixture if you feel necessary).
Cover and chill the custard, preferably overnight, until completely cold. (2-4 hours will suffice) Churn in an ice cream machine according to manufactures' instructions.
Crispy Banana Bread Chunks
Cut banana bread into small chunks (1/2 inch cubes).
Whisk together warm butter and brown sugar until the sugar is melted.
Toss the bread chunks in the butter mixture and spread out on a baking sheet lined with parchment paper.
Bake at 400 degrees for 25 min, flipping the chunks every 5 minutes so they crisp up on all sides. Let cool until completely cold.
Once ice cream is churned, swirl and layer with crispy banana bread chunks and dulce de leche into a freezer safe glass or plastice container. Enjoy all year round on a waffle cone or sandwiched between fresh gingerbread cookies!