Preheat the oven to 350 degrees F (175 degrees C).

Combine flour, eggs, pumpkin, peanut butter, salt, and cinnamon in a bowl; stir with a spatula until combined.

Transfer mixture to a work surface and work it with your hands until mixture starts to come together. Add 1 teaspoon water at a time (only if needed) to help make the dough workable, but don't add too much as it should be dry and stiff.

Roll the dough to a thickness of 1/2 inch. Cut into 1/2-inch pieces and transfer to a baking sheet.

Bake in the preheated oven until dog treats are golden brown and crunchy, about 40 minutes. Let cool before serving to your dog.