I adapted this recipe from one that appeared in Bon Appetite magazine many years ago. I took out the Chametz and made it pareve,  so I could use it on Passover. This four layer cake with a dark chocolate, extra shiny, glaze, makes a spectacular presentation and slices into about sixteen servings. It is dense, chocolaty and has a filling of strawberry butter cream to delight your taste buds. I have made it ahead and frozen it in a cake keeper. It has become easier to find kosher for Passover powdered sugar if you are concerned about this. I find that when it comes to Passover desserts, I need to devote one whole day to them, as they are time consuming.
For best results, bake the cake layers, make the butter cream, and assemble those parts in the morning. Refrigerate the cake for about 6 hours before you glaze it. The glaze comes out best if you pour and smooth the sides only once. The super shiny surface of the glaze will mar if you start fooling with it once you pour it.
1 and 3/4 cup unsalted margarine at room temperature
2 cups sugar
2 teaspoons vanilla
1/4 teaspoon salt
12 ounces imported bittersweet chocolate
Preheat oven to 375º. Melt the chocolate in a double boiler and set aside to cool slightly. Grease four 9 inches round cake pans. Line bottoms of the pans with parchment paper rounds, grease parchment. In a mixing bowl, cream the margarine, add the sugar, and beat until light and fluffy. Add the eggs one at a time beating until fluffy. Using a rubber spatula stir in the melted chocolate, and then the pecans. Divide batter into the four prepared pans. Bake until tester comes out fudgy but not wet, about 22 minutes. Cool on racks. After 10 minutes run a knife around the edges of the cakes to release them. Invert the brownie cake layers very carefully onto cooling racks. If one cracks a little, don’t worry you can still use it. Leave the layers to cool and proceed with the butter cream.  
Strawberry butter cream
1 & 1/4 cup unsalted margarine at room temperature
2 cups Passover powdered sugar
4 egg yolks
1/2 cup pureed fresh strawberries
3 tablespoons strawberry preserves
Easy chocolate glaze
3 oz semisweet chocolate
1/2 cup water
3/4 cup unsalted margarine
3 tablespoons safflower oil
3/4 cup unsweetened cocoa powder
1/2 cup plus 2 tablespoons sugar
One pint of perfect strawberries, washed, dried and trimmed flat.
Heat chocolate, water, margarine, and oil in a bowl set over a sauce pan of simmering water, until the chocolate and margarine melt. Remove the bowl from the top of the sauc pan. Add the cocoa and sugar to the melted chocolate, and stir until sugar dissolves and glaze is smooth. Let the glaze cool until thickened slightly but still pourable.
Arrange one cake layer, bottom side up, on a platter. Slide strips of waxed paper under cake. Spread one third of the butter cream over the first layer. Repeat with remaining layers ending with the last cake layer bottom side up. Cover and refrigerate for six hours. Pour glaze over cake, slowly controlling the flow as evenly as possible. Place the cake in the refrigerator and let the glaze set up a little more. Lastly, arrange large whole strawberries on top. Remove the messy waxed paper with the chocolate drips from around the base. Keep the cake refrigerated until 1 hour before serving.
Note: if your home is kosher; margarine, cocoa, oil, chocolate and other ingredients must be purchase certified kosher for Passover