Scalding the milk: Heat milk in a small saucepan until steaming or 180F. Remove from heat and let cool to just barely lukewarm (105F) or room temperature.
Plump the raisins (if using): Place raisins in a small bowl. Cover with very hot or boiling water and let stand 15 minutes. Drain and dry well before adding to dough.
Dissolve yeast in lukewarm water (about 105F) and the 1 tsp. sugar. in a small bowl. Let stand for 10 minutes.
In a large bowl or the bowl of a stand mixer with a kneading hook, combine the scalded milk, softened butter, 1/4 cup sugar, salt, vanilla and lightly beaten eggs. Add the yeast yeast mixture and mix to combine. Mix in the flour, 1/2 cup at a time, adding the spices with the third addition of flour, and the raisins/peel/currants with the next addition of flour, making sure the fruit is well covered with flour before mixing in.
Start kneading with hands or mixer, adding only enough flour to keep dough from sticking. Knead at least 5 minutes. Place dough into a greased bowl, sprinkle lightly with flour, cover with a damp cloth and leave in a warm, draft-free place until doubled in bulk.
Punch down dough. Cover again with flour and damp cloth and leave to rise another 30 minutes.
Preheat oven to 350F. (not fan assisted)
Divide dough into 9 equal-sized pieces. *I like to weigh the dough and divide that number by the number of buns I want to make, then weigh out each piece to that weight. That way all the buns will be exactly the same size.
Place balls into a greased 8x8-inch baking pan, in 3 rows or 3 buns. (For 9x13-inch pan, place in pan in 6 rows of 3). Cover pan with a clean towel and let rise until doubled.
Bake in a preheated 350° F. oven for 35-40 minutes or until golden brown and hollow sounding when tapped (or at least 195F when tested with an instant read thermometer). *Check them at 25-30 minutes and cover loosely with aluminum foil for the last part of baking, if already browned enough. They can seem "done" at about 30 minutes, but are probably not. Baking time should be at least 35-40 minutes).
Meanwhile, prepare the sugar glaze by stirring together the sugar and hot water.
Remove from oven and immediately brush tops of buns with the sugar glaze.
Allow buns to cool for 8-10 minutes in pan, then remove (in one large piece) to a cooling rack to cool completely. (Do not separate buns until ready to eat, to keep them nice and soft inside).
Once cooled or before serving, prepare the icing by beating together all the icing ingredients. Start with 2 tsp cream or milk and add more, a tiny bit at a time, until icing is piping consistency. Use a pastry bag or a ziploc bag with the corner snipped off to pipe a cross of icing on top of each bun.
To get the 1/2 egg, lightly beat 1 whole egg in a small bowl, then discard half of it.
You can use any combination of raisins, currants and/or peel, as you like, or just use all of one, if you prefer. just keep it to the total amount specified.
If you prefer a flour cross on your hot cross buns, simply mix up 1/2 cup all purpose flour and 5 Tbsp of water and pipe on top of buns before baking.
If you like a spicier hot cross bun, you can increase the spices to 1 tsp of each.Be sure to read the Ingredient and Cook's Notes above the recipe card, where I share more tips for making this recipe.