Heat 3/4 cup plus 2 tablespoons oil in a saucepan over medium heat. Add flour; reduce heat to medium-low. Cook, stirring frequently, until golden and thickened, 10 to 15 minutes. Let cool briefly.
Combine water and sugar in a separate saucepan over medium-high heat. Bring to a boil. Stir in rose water and saffron. Add the flour mixture. Cook and stir until thickened, 1 to 2 minutes at most. Serve halva with crushed pistachios and almonds sprinkled on top.
