Melt the buttery spread in a heavy bottomed sauce pan. Add the gluten free flour and stir for a few minutes. Make sure to stir well to remove any lumps.
Slowly drizzle in the non-dairy milk. Stir constantly until it starts to thicken.
Add the cocoa, sugar, and salt, and whisk thoroughly. Keep stirring until it is the desired consistency. Don’t let it boil. If it starts to get too thick, drizzle in a little more non-dairy milk.
Turn the heat down, and add the chocolate chips and vanilla extract. Stir until the chocolate chips are melted.
If you have some lumps from the flour, you can use an immersion blender to blend this sauce until it's smooth.
Notes
Store chocolate sauce in the refrigerator in an airtight container.Use any non-dairy milk that works for your needs, but try to choose a neutral tasting milk.