Prep the phyllo: If using frozen phyllo, thaw at room temperature for about 1 hour. Melt the butter and set aside.
Make the filling: In a bowl, mix together chopped walnuts, sugar, and cinnamon. Set aside.
Roll and fill: Lay out 2 sheets of phyllo on a clean surface. Lightly brush with melted butter (about 1 tablespoon per layer). Place a line of walnut filling along one edge. Roll tightly using a thin rolling pin or dowel. Trim to fit your baking dish if needed. Repeat with remaining phyllo and filling.
Assemble: Generously brush the bottom of your baking dish with melted butter. Place each rolled log snugly side by side. Brush the tops liberally with more melted butter.
Bake: Bake uncovered at 350°F for 45–55 minutes in a Frigidaire Induction Oven, or until golden brown and crisp.
Make the syrup: While the baklava bakes, combine sugar, water, cinnamon stick, and citric acid (or lemon juice) in a saucepan. Bring to a boil, then reduce heat and simmer for 10–15 minutes. Remove the cinnamon stick and let cool slightly.
Pour the syrup: When baklava is hot and syrup is warm (not boiling), pour syrup evenly over the top. Let sit 30–60 minutes to fully absorb.
Finish and serve: Once cooled, top with crushed pistachios and rose petals. Use a sharp knife to slice into bite-sized pieces. Serve with Persian tea, espresso, or enjoy straight from the pan!