Lightly grease the bottoms and longer sides of a 9 x 5 loaf pan. Generously grease the shorter ends with butter. Line with parchment paper, leaving about a 2-inch overhang on the longer sides.
In a small bowl, combine the Redpath® Golden Yellow Sugar with the lime zest. With clean fingers or the back of a spoon, rub the zest into the sugar until sugar is moist and fragrant. Set aside to allow flavours to meld.
Layer the stale bread on the bottom of the loaf pan (see Chef’s Tips). Build the layers and slice the bread to size with the undipped, dry bread; assembly will be easier when dipping and building the layers if this is already done. Ensure the slices of bread touching the shorter ends of the loaf pan are sliced or straight to create an even and clean edge.
Remove the sliced bread from the loaf pan in the order it is laid out in the pan and place on a cutting board or platter. The top layer in the pan should now be the bottom layer on the board and vice versa. There should be 4 layers of bread.
In a medium bowl or large measuring cup, whisk together eggs, yolk, vanilla extract, cinnamon, and salt until well combined. Add in the brown sugar mixture and whisk well. While whisking, slowly pour in the half and half. Whisk until mixture is homogeneous and sugar is dissolved. Pour half of the mixture into a dish.
Dip the slices from the bottom layer into the custard, dipping both sides and all edges. Whisk in between dipping slices to ensure zest and cinnamon are evenly distributed.
Lay each piece carefully into the bottom of the loaf pan. Scatter about a third of the blueberries (about 60 grams) and/or haskap berries onto the bread, followed by scattering ¼ of the small butter pieces (about 10 grams) over the blueberries and bread. Repeat process with the remaining bread slices. Level and even out the last layer by gently pressing down on the slices of soaked bread. Whisk together the remaining custard and evenly pour the custard over the entire loaf.
Dot the surface with the last pieces of butter. Cover with foil and place into the fridge to chill and allow the bread to fully absorb the custard; at least 4 hours, but preferably overnight.
In a small bowl, whisk together the Redpath® Icing Sugar and salt until evenly distributed. Add in the pure maple syrup and whisk until smooth. Cover and set aside until needed.
Preheat oven to 350°F (177°C). Remove loaf from the fridge while the oven is preheating.
Place the loaf into the preheated oven; bake covered for 20 minutes. Rotate pan and remove foil and bake for another 20 minutes or until loaf has puffed up and the top is crisped and golden brown in colour. Remove from the oven and place onto a wire cooling rack to cool slightly; 10 minutes.
Place a cutting board or platter on top of the loaf pan. Wearing an oven mitt, place your gloved hand under the loaf pan and the other hand on the bottom of the cutting board or platter. Carefully flip the pan and cutting board together and invert the loaf pan. Lift off the loaf pan and gently peel away the parchment paper.
Garnish the top with fresh blueberries, if desired. Drizzle loaf with the maple glaze. Slice with a serrated (bread) knife. Serve plain or dusted with Redpath° Icing Sugar and/or maple syrup.