In the evening (7-9pm), mix together 25 g sourdough starter, 25 g sugar, 65 g warm water, and 85 g bread flour. Cover the jar loosely and let ferment on the counter until morning.

Set out 84 g unsalted butter for the main dough so it's softened by morning.

In the morning, mix 35 g bread flour and 175 g whole milk in a microwave-safe bowl. Microwave in 30-second intervals, stirring between each, until thickened and reaches 150°F (65°C). Let rest on the counter (or in the fridge) until the mixture has cooled down to below 80°F (26°C).

In a stand mixer bowl fitted with a dough hook, combine All of the sweet starter, All of the tangzhong, 150 g pumpkin purée, 25 g cool water, 1 egg, 1 tsp cinnamon, 1 tsp pumpkin spice blend, 1 tsp vanilla extract, 1 tsp maple extract, 515 g bread flour, and 12 g sea salt. Mix on the lowest speed for about 3 minutes, or until ingredients are fully incorporated. Then, increase the speed slightly for 7-15 minutes, or until the dough's surface is smooth.

At a low speed, add 84 g unsalted butter one pat at a time, waiting for incorporation between additions. Once the butter is fully incorporated, continue mixing at a low speed for about 2 minutes more, or until very smooth.

Transfer your soft, smooth dough to a lightly oiled container, cover, and let rise in a warm place (75-85°F/24-29°C) for 3-5 hours.

Place the container of dough in the fridge until bedtime. Set out 142 g unsalted butter so it's softened to make your filling later.

Right before bed, pull your chilled dough out of the fridge. Grease a 9x13 baking pan.

In a medium-sized bowl, whisk together your filling: 142 g unsalted butter, 175 g brown sugar, 8 g cinnamon, 8 g pumpkin spice blend, and 40 g pumpkin purée.

Generously flour your work surface and dump out the dough. Roll into a square that’s about 19.5"x19.5". Spread filling on dough with a spatula, leaving a 1-inch gap at top.

Cut the sheet into strips and roll up each strip, brushing a little milk or cream along the top edge to help the dough seal to itself. Place the shaped rolls in your baking pan.

Cover your pan with plastic wrap, and let proof on the counter overnight.

In the morning, preheat your oven to 350°F (175°C). Warm 85 g half & half in the microwave and pour over the cinnamon rolls. Bake for about 25-30 minutes, or until the internal temperature is around 195°F (90°C).

When the cinnamon rolls are done baking, whisk together 20 g melted butter, 20 g maple syrup, 1 tsp maple extract, and a pinch of salt in a small bowl. Brush the wash on top of the hot cinnamon rolls when they come out of the oven.

For the icing, whisk together 28 g unsalted butter, 170 g cream cheese, 1 tsp maple extract, and 20 g maple syrup. Then, add 200 g powdered sugar and a pinch of salt. Let the rolls cool for about 5-10 minutes before adding your icing.