Warm the milk until lukewarm (105–115°F). In the bowl of a stand mixer fitted with the dough hook, combine 1 cup of the flour, yeast, sugar and salt. Add the warm milk, melted butter and egg and mix on low until incorporated.
Gradually add the remaining flour, a little at a time, until a soft dough forms. Knead on medium speed 5–7 minutes until smooth and slightly tacky (add up to 1 tbsp water or flour if needed).
Transfer dough to a lightly oiled bowl, cover with plastic wrap or a damp towel, and let rise in a warm spot until doubled, about 60 minutes.
While the dough rises, mix the filling: stir together the peanut butter, brown sugar, cocoa, cinnamon and cardamom until spreadable. Fold in the mini chocolate chips last so they stay intact.
When the dough has doubled, punch it down and turn it onto a lightly floured surface. Roll it into a roughly 12x16-inch rectangle about 1/4-inch thick.
Spread the peanut butter filling evenly over the dough, leaving a 1/2-inch border on one long edge. Starting at the opposite long edge, roll the dough tightly into a log and seal the seam by pinching.
For neater slices, wrap the log in plastic and chill 10–15 minutes to firm slightly. Unwrap and slice into 12 equal rolls with a sharp knife or dental floss.
Arrange the rolls in a lightly greased 9x13-inch baking pan, cut side up, leaving a little space between them. Cover loosely and let rise until puffy, about 20–30 minutes.
Preheat the oven to 375°F. Bake the rolls in the center rack for 16–18 minutes, until golden brown and set. Avoid overbaking so they stay tender.
While the rolls bake, whisk the powdered sugar with 2 tablespoons milk to a pourable glaze (add the third tablespoon if you prefer thinner). Warm the 2 tbsp peanut butter and thin with a teaspoon of milk for an optional drizzle.
Remove the pan from oven and let the rolls cool 8–10 minutes. Drizzle with the glaze and the peanut butter, then serve warm or at room temperature.