In a medium bowl, combine the gluten-free flour blend, salt, baking soda, and pumpkin pie spice. Mix and set it aside.
In the bowl of a stand mixer (or a large bowl with a hand mixer), add the softened butter, granulated sugar, brown sugar, and beat for a couple minutes until fluffy and light in color.
To it, add the egg yolks and cream again. Add the pumkin purée, vanilla, and mix until combined. Your mixture may look slightly curdled, but don't worry.
Add the dry ingredients and mix on low speed until you see no pockets of dry ingredients. Add the white chocolate chips and mix again. Cover the bowl and let it chill in the fridge for at least 2 hours.
Preheat your oven to 375°F (190°C) and line a baking sheet with parchment paper.
Scoop out the chilled dough onto the baking sheet using a cookie scoop or two spoons, and flatten the top very slightly to ensure an even bake. Leave 2 inches in between each dough ball to prevent them from spreading and sticking to each other in the oven. You can top them with extra chocolate chips if you want the chips to be showing after they're baked.
Bake the cookies for 8 or 9 minutes. They may look underbaked but they will continue baking after you take them out of the oven. Let the cookies cool for 10 to 15 minutes on the baking sheet before taking them off onto a wire rack to cool completely.