Preheat oven to 350°.
Topping
In a small bowl, stir together sliced almonds, almond oil, brown sugar, and remaining 1/4 tsp. salt. Set aside.
Cake
Microwave chocolate and butter in a large microwave-safe bowl at HIGH 1 to 1-1/2 minutes or until melted, stirring once. Whisk in sugar. Add eggs, 1 at a time, whisking just until blended after each addition. Whisk in flour, next 3 ingredients, and 1/4 tsp. salt.
Pour batter into a greased (with butter) 2-qt. baking dish. Sprinkle almond mixture over cake batter. Bake at 350° for 30 minutes. (Center will be soft.) Cool on a wire rack 5 minutes. Serve warm.