In a large mixing bowl, combine water, 1 teaspoon of the sugar, and yeast. Whisk to combine and set aside for 5 to 10 minutes, or until frothy and bubbly on the surface.
Add the remaining sugar, milk, and egg to the yeast mixture. Whisk to combine. Add in the flour, cinnamon and nutmeg. Mix everything together until a dry, shaggy dough starts to form.
Add your butter to the dough, and mix until it starts to stick together and form a rough ball of dough. Turn the dough onto a floured work surface, and knead for about 5 to 10 minutes (adding flour as needed to prevent sticking), or until it's smooth and elastic. It should be soft and slightly tacky, but the dough shouldn't stick to your hands. * You can also do this step in a stand mixer fitted with a dough hook attachment (on medium speed). Sprinkle the raisins or currants over the dough. Knead again until the raisins are evenly distributed throughout the dough.
Shape the dough into a ball, and place in a large, lightly oiled bowl. Cover, and set aside in a warm place to rise for about 1 hour, or until nearly doubled in size.
Line a 9x13 inch baking dish with parchment paper, and set aside.
Once the dough has doubled in size, uncover and turn it onto a lightly floured work surface. Divide the dough into 12 equal portions, and roll each portion into a smooth ball.
Arrange the balls of dough in your parchment lined baking dish, leaving a bit of space in between each one for them to expand. Cover the shaped dough, and set aside again until about doubled in size (about 45 minutes).
Preheat your oven to 350°F.
Make the flour mixture for your crosses: In a medium bowl, mix together flour and 3 to 4 tablespoons of water until you get a thick, pipe able paste. Transfer the flour mixture to a small piping or plastic bag, and cut a small hole from the tip.
Uncover your risen buns, and pipe crosses using the flour mixture. Bake in the center of your preheated 350°F oven for 25 to 30 minutes, or until golden brown on top.
Make the glaze: While the buns bake, combine granulated sugar and water in a medium saucepan. Place the pan on a stove burner set to medium heat, and warm until the sugar has fully dissolved. Set aside to cool for 5 to 10 minutes before glazing.
While the buns are still hot, brush the tops with the glaze. Set aside for about 15 to 20 minutes to cool slightly and soak up the glaze before serving.