Braided banana bread danish

based on this, after Evan requested banana bread for passing his qual(!) and Sarah O recommended the original version

EDIT: amounts in parentheses are what I used when I made it again two days later. This is the amount of chocolate and nuts with the higher amounts:

dough:
3/4 c warm water
1 T yeast
1 t sugar
1/2 c flour
1 stick butter
2 overripe bananas (3)
2 eggs
1/2 c greek yogurt (1/3 c, but only because that's all there was)
1/4 c brown sugar
2 t salt
2 t vanilla
zest of 2 tiny Meyer lemons (2 t lemon marmalade)
1 t cinnamon (2 t, plus 1/2 t allspice)
1 c wheat flour
4.5 c white flour (5 c)

Combine the first four ingredients in the kitchenaid bowl. Let sit while you mash the bananas with a potato masher and soften the butter. Mash the butter, eggs, and yogurt into the bananas until everything is as smooth as it's going to get. Add the banana-dairy mixture to the sponge, add everything else except the flours, and stir with the kitchenaid until combined. Add the flours a cup at a time, stirring with the dough hook for several minutes, until something elastic like a dough but extremely soft like a batter forms. Transfer to a greased bowl, cover with plastic, and let rise until doubled. (If after an hour it's not even thinking about rising, stick it in the oven with a pan of boiling water.)

filling:
2/3 c, i.e., 5 oz cream cheese
1/4 c white sugar
1/4 c greek yogurt
1/4 c white flour
2 t lemon juice from 1-2 Meyer lemons
1 t amaretto
1/3 c walnut halves (2/3 c)
1/3 c chocolate chips (2/3 c or even more)

Stir together everything except the chocolate and nuts until fairly smooth. Let sit on the counter to soften while the dough rises. Chop together the walnuts and chocolate chips.

Put a bunch of flour on a surface. Pour the dough onto the flour and gently press and fold over a few times. Cut in half and set one half aside (on a little bed of flour). Press the first half into a rectangle and transfer to a piece of parchment paper. Roll out into a large rectangle, cut strips as described, spread with half the filling and sprinkle with half the chocolate and nuts, and fold over the strips as described. Gently transfer the loaf + parchment to a baking sheet. Repeat with the other half. I had some extra filling, so I dolloped a little bit onto each of the leftover corners and pinched them up into little pockets. Cover and let rise for an hour or a bit less until nice and plump.

topping:
1 egg
2 t water
turbinado (or the largest-grain sugar you have)

Preheat the oven to 375F while the dough is rising. Beat together the egg and water, and brush on the loaves. Sprinkle with sugar. Bake for 27 min, switching racks halfway through. Carefully transfer to cooling racks.