Whisk together flour, cinnamon, pumpkin pie spice and salt.
Melt the salted butter in a saucepan. Add water, pumpkin purée, brown sugar and vanilla. Bring to a gentle boil.
Reduce heat to low and immediately add the flour mixture. Stir vigorously for 1–2 minutes until a thick dough forms.
Transfer to a bowl and cool for 10–15 minutes.
Beat in the eggs one at a time until the dough is smooth, glossy and sticky.
Transfer to a piping bag fitted with a large star tip.
Pipe approximately 20 churros or pumpkin-shaped spirals onto parchment squares.
Heat approximately 2 inches of avocado oil to 175°C (350°F).
Carefully lower the parchment squares into the oil. Remove the parchment after 10–15 seconds using metal tongs.
Fry for 2–4 minutes, turning halfway, until golden and crispy.
Transfer to a paper towel-lined rack.
Mix the sugar, cinnamon and optional pumpkin pie spice. Toss the warm churros in the mixture until coated.
Serve warm.
