Warm the milk to 105–110°F. Combine it with the yeast and 1 teaspoon of the measured granulated sugar. Let stand for 5–10 minutes, until a creamy foam forms across much of the surface.

Add the remaining granulated sugar, mashed banana, eggs, softened butter, and salt. Mix until mostly combined. Add the flour gradually while mixing on low. Knead with a dough hook on medium-low for 6–8 minutes, or by hand for 9–11 minutes, until the dough is smooth, elastic, and slightly tacky but releases from a clean fingertip without leaving wet dough behind.

Coat a clean bowl with the neutral oil. Shape the dough into a ball, turn it once in the bowl, and cover. Let rise in a warm, draft-free place for 60–75 minutes, until approximately doubled and a lightly floured fingertip indentation slowly springs partway back.

Lightly grease a light-colored 9×13-inch metal baking pan. Mix the softened butter, brown sugar, cinnamon, and salt into an even, spreadable paste.

Gently deflate the dough and roll it on a lightly dusted surface into a 16×12-inch rectangle. Spread the filling evenly to within 1/2 inch of the far long edge. Sprinkle with the optional nuts only when using them. Starting from the long edge nearest you, roll into a snug log without stretching and pinch the seam to seal.

Cut the log into 12 equal rolls, approximately 1 1/3 inches wide. Arrange them cut-side up in the prepared pan in 3 rows of 4, leaving small gaps between the rolls.

Cover and let rise for 35–45 minutes. After the first 15 minutes, position a rack in the center of the oven and preheat to 350°F. The rolls are ready when visibly expanded, nearly touching, and a gentle fingertip press springs back slowly without collapsing.

Bake on the center rack at 350°F for 25–30 minutes, until evenly golden, the center roll no longer looks wet or compressed between its spirals, and its internal temperature reaches 190–195°F. Cover loosely with foil during the final 5–8 minutes if the tops brown too quickly. Cool in the pan on a wire rack for 10 minutes.

Beat the cream cheese and butter until smooth. Mix in the powdered sugar, vanilla, and salt. Add milk 1 tablespoon at a time only as needed for a thick, spreadable consistency. Spread over the warm, not piping-hot, rolls and serve.