In a saucepan, bring the blueberries, sugar, and lemon juice to a boil, stirring frequently. Simmer for 5 minutes. Let cool and refrigerate until the mixture has cooled, about 1 hour.
Line six 125 ml (½ cup) ramekins with lightly oiled plastic wrap.
With a 7-cm (2 ¾-inch) cookie cutter, the same diameter as the inside of the ramekins, cut 18 disks of bread (see note). Keep the remaining bread for another use (see note).
Evenly spread 15 ml (1 tablespoon) of the blueberry sauce into each ramekin. Cover with a disc of bread. Repeat with the sauce and bread to make 2 additional layers. Keep the remaining sauce for garnish.
Fold the plastic wrap back over the pudding to cover. Place the ramekins on a baking dish and place a small can or ramekin filled with dried beans on each pudding to weigh them down.
Refrigerate for 4 hours or overnight. Unmould and remove the plastic wrap. Invert onto plates and top with whipped cream. Garnish with the remaining blueberry sauce.
If the bread slices are large enough, it will take only 12. You can cut 1 ½ discs in each slice. You only have to place two half-discs of bread in the middle layer of the puddings.
Dry the scraps to make breadcrumbs in a food processor or simply make bread cubes that you can turn into croutons.
Recipes with the "Healthy Pick" stamp have been evaluated by a registered dietitian member of the Ordre professionnel des diététistes du Québec.