In a medium bowl, mix the pumpkin purée, pumpkin spice, salt, and liquid stevia. Gradually add the oat flour, stirring until just combined.
Take small portions of the mixture and roll them into bite-sized balls. Place them on the prepared tray. (If the mixture sticks, lightly oil your hands!)
Melt the dark chocolate in a microwave-safe bowl, heating for 30 seconds, then stirring for 1 minute. Continue heating in 10-second intervals, stirring until fully melted. Keep warm while assembling.
Dip each pumpkin ball into the melted chocolate using two forks, allowing excess chocolate to drip off. Place back on the wax paper. If desired, sprinkle with flaky sea salt. Repeat until all truffles are coated.
Freeze for 5-10 minutes or refrigerate for 15-20 minutes until the chocolate hardens. Store in the refrigerator until ready to enjoy.
Notes
See Notes for homemade pumpkin spice and chocolate recommendations.