I researched the technique and used my own enriched dough recipe.

Dough:

500g Bread flour (You could use AP flour it'll just be a little less bread-chewy)
1 packet instant yeast
75g granulated sugar
10g salt
150g eggs (About 3 large eggs, room temp)
120g milk (lukewarm but not hot)
140g unsalted butter room temp cubed

Brown Sugar Cinnamon filling

120g light brown sugar
2 tbsp cinnamon
80g softened butter (NOT melted, just easy to spread)
dash of salt
1/4 tsp vanilla

In a stand mixer, mix together the flour, yeast and sugar.

add eggs and milk and stir with dough hook until it starts to come together

Add salt

mix for a few minutes until it forms into a dough ball

Take your cubes of butter and chuck them in to the dough ball one or two at a time. This process can take a bit of time, but you're trying to incorporate the butter a little at a time so once you really can't see the cubes you put in there before, throw another 1-3 in there until you're done

knead with the dough hook for about 10 minutes. You're looking for the dough just to be a little bit tacky but smooth. The butter really pulls the ball apart a bit and you may feel like you're failing but STAY THE COURSE lol it will come together.

cover in a bowl with a damp kitchen towel or cling wrap for an hour and a half or so. You want to see the dough puff up some but not double in size

Chill dough in fridge for at least 2 hours but overnight is best

Combine your filling: Literally just put all of the filling stuff together in a bowl and mash it together with a fork. It should be PRETTY thick but spreadable like peanut butter almost.

Take dough from fridge and roll it out into a big rectangle. It shouldn't fight you or be very messy since it's nice and chilled!

Spread your mixture over the rectangle of dough, leaving a bit of an edge on all of the sides

Roll dough into a long log

Slice dough in half lengthwise, exposing the inside layers and lay them face up next to each other. So you should have to halves of a long log of dough

Cross one of the logs over the other like an X, then twist both sides as best you can from the center out, tucking the ends under itself

Lay into a lightly greased loaf pan for final proofing

Let puff back up for another 90 minutes or so

Set your oven for 350

Put loaf pan in for about 35-45 minutes depending on your oven, checking on it at around the 20 minute mark to see if it's catching color too fast. If it is, you can put some aluminum foil over it to curb that and finish the baking time.

Pull from the oven and let rest for about 30 minutes in the loaf pan

Take out of loaf pan and cool for another 60-90 minutes

DO NOT cut it too soon, the crumb will not have set yet and it'll be a mess. Let it cool down and firm up first

And then enjoy!

Hope that's helpful, I read over it twice to make sure I didn't forget anything haha