Stir yeast and sugar into warm water, allow to stand for 10 minutes – it should get very bubbly.
In a large mixing bowl, combine flour and salt. Pour in yeast mixture, stir well to combine.
Dump dough out onto a floured surface, knead until soft and elastic, 5-10 minutes. (OR: mix it in a stand mixer with a dough hook for 5 minutes or so - That's how I do it!)
Once dough is fully kneaded, place in a greased bowl, cover with plastic wrap, and allow to rise for one hour, or until doubled in size.
Once dough has doubled in size, roll dough out on a floured surface. Aim to make it a large rectangle, say 15 x 20″ or so.
Use a pastry brush to spread melted butter all over the dough – you might not use it all, that’s ok.
Mix together the sugar, and spices, sprinkle about ⅔ of it evenly over the melted butter,
Finely chop the apples, arrange apple pieces over the spiced sugar mixture. Sprinkle most of the remaining sugar mixture over the apples, reserving 1-2 tablespoon of sugar.
Starting with one of the longer edges, tightly roll the dough up.
Generously grease or spray a 9x 13″ baking pan. Pour any remaining butter in the bottom, spreading evenly before sprinkling with remaining sugar mixture.
Using a very sharp knife, slice the roll into 12 even rounds.
Carefully place each roll into the pan, spacing them evenly.
Cover pan with plastic wrap, allow to rise one more time – about 45 minutes. While waiting for the buns to rise, heat oven to 350F.
(This is what they looked like after the final rise!)
Once final rise is over, pop the pan in the oven and bake for 30-35 minutes, or until golden brown and perfect.
Allow to cool for a few minutes while you make the glaze:
Mix together softened butter, vanilla extract, maple syrup, and salt, until smooth.Add about ½ cup of powdered sugar, whisking until smooth. Add remaining powdered sugar, about ¼ cup at a time, until you have a thick, paste. If it's not smooth, microwave for 15 seconds and stir well. Drizzle or spread over hot Apple Cinnamon buns, allowing it to melt and ooze a little. If glaze has thickened, microwave for 15 seconds and stir again, immediately before drizzling.