Preheat the oven to 375°F (190°C) and line a baking sheet with a silicone baking mat or parchment paper.

Drain the ricotta: spoon it into a fine-mesh sieve set over a bowl and let it drain for 10 to 15 minutes, pressing gently to remove excess liquid.

In a stand mixer bowl (or a large bowl with a hand mixer), beat the softened butter and sweetener until creamy. Add the drained ricotta and pumpkin puree and beat until smooth.

In a separate bowl, whisk together the almond flour, flaxseed meal, baking powder and pumpkin pie spice. Add to the mixer bowl and beat until fully combined. The dough will be thick and soft.

Use a 2-tablespoon cookie scoop to portion the dough onto the baking sheet, about 2 inches apart (you should get about 16 cookies). Flatten each mound slightly with the back of a spoon or damp fingers, since the cookies won't spread much.

Bake for 10 to 12 minutes, until the edges start to darken. Leave the cookies on the baking sheet for 10 minutes (they're very soft when hot), then transfer them to a cooling rack to cool completely.

Store in an airtight container in the refrigerator.