For the berries, mix water and sugar together and add the rest of the ingredients. Bring mixture to a boil and reduce to a thickened syrup.

For the custard, beat the sugar and egg yolks together with a whisk for 2-3 min. until the mixture is pale yellow. Beat in the flour. Continue beating and slowly add the boiling milk a dribble at a time in the beginning. Pour into a saucepan and over medium heat stir with a whisk. Bring sauce to a boil, if it gets lumpy just continue to whisk and it will smooth out. Bring the heat down now to medium low and cook whisking for 2-3 min. Make sure you reach all the sides of the pan and don't let the custard scorch.

Remove from the heat and whisk in the butter and almond extract. If the custard is not used immediately dot the top with butter. This will prevent it from forming a skin.

Fill the tart shells with a dollop of the custard and top with the berries just before serving. Refrigerate the custard tarts and berry topping separately.