For the lemon chiffon cake:
1. Preheat oven to 375°F (190°C). Grease the bottoms of two 8 inches (20.5 centimetres) cake pans, dust with flour and tap to remove excess.
2. In a large bowl whisk together the flour, 1 cup (200 grams) of Redpath® Granulated Sugar, baking powder and salt; set aside.
3. In a large bowl, with an electric mixer on medium speed, beat the egg whites and cream of tartar until foamy. Add the remaining ¼ cup (50 grams) of sugar in a slow, steady stream. Continue beating until the eggs hold firm, glossy peaks, 6 to 7 minutes; set aside.
4. With electric mixer on medium, beat together the egg yolks, oil, buttermilk, lemon zest, lemon juice and lemon extract until smooth.
5. Add the wet ingredients to the dry ingredients and stir until fully combined.
6. Using a rubber spatula, gently fold the egg whites into the batter in three additions, mixing each addition just until no streaks of white remain. Divide evenly between the prepared pans.
7. Bake until centre springs back when pressed, or an inserted skewer emerges clean from the centre, 25 to 30 minutes.
8. While cakes are baking invert 2 sheet pans on the counter, spacing them about 6 inches (15 centimetres) apart. Suspend cakes upside down between the two inverted sheet pans and allow to cool for 20 minutes.
9. Run a paring knife around the edges to loosen the cakes, removing from pans to cool completely.
For the vanilla bean buttercream frosting:
1. Place the butter in a large bowl and beat with an electric mixer, on medium, until smooth. Reduce speed to low and beat in Redpath® Icing Sugar, 1 cup (120 grams) at a time, until smooth. Beat in vanilla bean seeds, cream and salt. Increase speed to high, mixing for 2 minutes.
For the assembly:
1. Using a sharp, serrated knife, trim off the domed top of each cake. Place one cake, cut side up, on a cake turntable or level surface.
2. Place about ¾ cup (165 grams) of frosting on the cake, spreading evenly with an offset spatula and pressing in raspberries. Spread ¼ cup (55 grams) of frosting over the berries to create an even layer. Top with second cake, cut side down, and press gently.
3. Using an offset spatula, spread a thin layer of frosting over the top and sides of the cake to seal in the crumbs. Chill in refrigerator for 15 minutes.
4. Place a large spoonful of frosting on the cake and smooth out an even layer with an offset spatula, allowing excess frosting to fall over the sides. Smooth the frosting down the sides to fully cover, adding more frosting as necessary. Turn the cake while spreading to create smooth sides. Keep the remaining frosting to make the buttercream flowers (you will have about 2 cups ((200 grams)) remaining).
5. Chill cake while preparing the buttercream flowers.
For the buttercream flowers:
1. Line a small baking sheet with parchment paper. Cut fifteen 3 inches (7.5 centimetres) squares of parchment paper.
2. Divide remaining frosting between 3 bowls. Leave one bowl of frosting white and tint the other bowls with your colour of choice (we chose light and golden yellow).
3. Fit a piping bag with the small closed star tip and fill with white frosting. Hold piping bag perpendicular to the parchment lined sheet, ½ inch (1.3 centimetres) from the paper. Squeeze piping bag to create a blossom, then release pressure, press down and pull up. Repeat to make 12 flowers about 1 inch (2.5 centimetres) in diameter.
4. Fit a piping bag with ½ inch (1.3 centimetres) plain round tip, and fill with the remaining white frosting; set aside.
5. Fit a second piping bag with the small petal tip, filling with tinted frosting. Place a small dollop of frosting on the flower nail and press on a parchment square. Hold the bag with the large end of the tip touching the centre of the paper. Squeeze the bag, while slowly turning the nail, to create a small rosette. Release and begin piping ribbon shaped petals around the rosette, overlapping each petal. Repeat to make about eight flowers one to two inches (2.5 to 5 centimetres) in diameter.
6. Fit the third piping bag with the medium closed star tip and with the second tinted frosting. Hold the piping tip about ½ inch (1.3 centimetres) above the a square of parchment. Squeeze bag slowly and, pressing lightly, pipe in an outward spiral. Ease the pressure on the bag and then gently press down and pull up to release. Repeat to make five flowers two to three inches (5 to 7.5 centimetres) in diameter. Freeze flowers for at least 20 minutes.
7. Clean out the piping bag with the small closed star tip and fill with any remaining tinted buttercream (if you mix colours, it's fine).
How to decorate the flower wreath cake:
1. Using the piping bag filled with the remaining white frosting pipe a circle on the top of the cake, ½ inch (1.3 centimetres) from the edge.
2. Decorate with the buttercream flowers, using white frosting to assist with adhering the flowers where necessary.
3. Use the piping bag, fitted with the leftover tinted frosting, to fill in the centre of the white blossoms and any gaps in the wreath.