Maple Bacon Waffle Donuts

3/4 cup lukewarm milk

1/4 cup sugar

3 teaspoons dried yeast

3 egg yolks

2 1/2 cups plain flour, plus extra

3 1/2 ounces chilled butter, cut into small cubes

5 slices of thick cut bacon

5 teaspoons maple syrup

2 tablespoons butter, melted

1/4 cup maple syrup

1 cup icing sugar