Grease a large loaf pan & add a parchment paper liner in the bottom
Make the Pumpkin Dough by combining all the dry ingredients together in the work bowl of your electric mixer *If you are not using Instant Yeast you will add the yeast to a small bowl with some of the warm (110℉) plant milk & let stand 5 minutes
Add the plant milk & pumpkin to all the dry ingredients in the bowl & mix with the dough hook ~ you may need to help it along with a spatula until it forms a soft mass, then let it knead for 5 minutes on medium speed
Add the softened vegan butter & mix just until it is all incorporated (total mix time is about 8 minutes)
Transfer the dough to a lightly oiled bowl covered & let rise to double in size in a warm spot (approx 1 hour)
Meanwhile prepare the poppy filling: First grind the poppy seeds in a spice grinder & set aside. This step is important to allow for the ingredients to blend to a paste rather than a gritty mixture & it also releases the flavor from the seeds
Now combine the plant milk with the sugar, cornstarch & pinch of salt in a medium sauce pot over medium to high heat whisking often to avoid scorching the bottom
Once the custard starts to bubble remove it from the heat & add the vegan butter, stir until it is melted then add the poppy seeds. Refrigerate the filling to cold
Once the dough has risen & the poppy filling is cold roll the dough out on a lightly floured surface to approximately 10" x 10"
Spread the poppy filling over the entire dough then roll it up jelly roll styleCut a slit down the center but keeping the ends intact then twist it and place it into the prepared loaf pan *see video linked above for visual Cover & let rise again approximately 40 minutes then preheat the oven to 350℉
Brush the top of the bread with your favorite wash & bake for 35-40 minutes then turn the oven down to 325℉ & bake for another 20 minutes or when an instant read thermometer is at 200℉
Cool the bread in the pan until you can safely touch it then turn it out onto a cooling rack to cool the rest of the way