Preheat the oven to 350 degrees.
For the dough, mix the oat flour, pumpkin pie spice, pumpkin puree, and date paste in a large bowl. The dough should be very thick and not too wet.
Press out 1/4 cup of the dough into 4 rectangular shapes on a nonstick or lined baking sheet. These are the bottoms of the poptarts.
Bake just the bottoms for 10 minutes.
While the bottoms are baking, make the filling by mixing the pumpkin puree, date paste, vanilla extract and pumpkin pie spice.
When the bottoms have baked for 10 minutes, set the pan on the counter and carefully (the pan is really hot!) spoon about 2 tbsp of the filling on top of each poptart bottom.
Measure out 1/4 cup of the remaining dough for each poptart top - shape it roughly with your hands, and place it on top of the filled bottoms, carefully sealing the edges with your fingers (remember, the pan is hot, so be careful!)
Use a fork to gently press the edges of the poptart to seal them together.
Bake the full poptarts for another 10 minutes.
Once they're done, allow the poptarts to cool on the pan for 20 minutes before removing.
Store leftovers in the refrigerator.
