Preheat the oven to 400°F (200°C). Place a rack in the center of the oven.
In a large bowl, whisk together the flour, farina, turmeric powder, milk powder (if using), and baking powder.
In a separate bowl, dissolve the sugar in the milk. Add the oil and melted butter, and stir to combine.
Gradually add the dry ingredients to the wet ingredients, stirring well until you have a smooth, evenly colored yellow batter.
Grease a 12-inch (30 cm) round baking pan generously with tahini.
Pour the sfouf batter into the prepared pan. Use an offset spatula to spread the batter into an even layer.
Scatter the pine nuts evenly over the surface of the batter.
Bake for 20–25 minutes, or until golden brown. Keep a close eye on the sfouf toward the end of the baking time, as ovens vary.
Remove from the oven and allow to cool completely. Cut into medium-sized squares or diamond shapes and serve.