Preheat the oven to 425°F. Line a baking sheet with parchment paper.
In a medium saute pan over medium heat, combine the ground pork, onion, minced garlic, and salt. Cook, breaking the pork into pieces with a wooden spoon, until no pink remains, about 10 minutes.
Add the artichoke hearts, tomato paste, red pepper flakes, and garlic powder and mix well to combine.
Add the spinach, cover, and cook for about 1 minute, until the spinach has wilted, then mix to combine.
Scoop the mixture into the mushroom caps, dust with the almond flour, and then drizzle a bit of olive oil over each stuffed mushroom.
Bake the stuffed mushrooms on a wire rack set on top of the lined baking sheet for 15 minutes, until the mushrooms are soft.
