Marimekko's brilliant floral patterns make this zesty orange cake extra cheerful. This cake has a few steps, so I like to spread out the work over a few days. Make the cake and filling on one day; fill, frost, and decorate the next.
12ounceschopped orange segmentsabout 3 large oranges
Orange food coloroptional
Orange buttercream and fondant instructions
2 ½-3cupsconfectioners’ sugar
2teaspoonsclear orange extractplus extra for painting
Milk or heavy creamoptional
1lbwhite vanilla ready-made rolled fondantI like Satin Ice
Red gel food color
Black gel food color
Orange gel food color
Small artists’ brush
Spray pans with flour-based baking spray, or grease and flour them.
Preheat oven to 325°F.
In a large mixing bowl, beat together the sugar, eggs, and oil. Add sour cream, vanilla, orange zest, and poppy seeds; mix until well combined.
Sift in 3 cups of the flour, the salt and baking powder. Mix on low speed until just combined. Add the buttermilk and mix until incorporated. Sift in the remaining 1/2 cup of flour and mix until combined. Scrape down the bowl and beat again briefly.
If making a triple layer cake, place two cups of batter in each 8-inch pan. If making a double layer cake, place 3 cups of batter in each 9-inch pan.
Bake for 25-30 minutes, or until the cakes spring back when pressed in their centers.
Let the cakes cool in pans for 5 minutes, then turn them out onto wire racks to cool completely.
In a small saucepan, bring the orange segments and water to a boil. Mash them as they cook with a potato masher or the back of a large spatula. Reduce heat. Simmer for 5 minutes. Remove from heat. Press oranges through a sieve; discard membranes and seeds and allow the mixture to cool. You should have 1 cup of cooked juice, if you’re short, fill the measure with prepared orange juice until it reaches 1 cup.
Wash the pan for reuse. Combine the sugar and cornstarch in the pan; stir in the cooled orange juice mixture and whisk until smooth. Bring the mixture to a boil and cook for 2 minutes or until thickened. Stir in the orange extract and orange food color, if using. Transfer the mixture to a separate bowl and let cool completely.
Make the buttercream
In a stand mixer fitted with the whisk attachment, mix together the butter and confectioners’ sugar. Begin on low speed and then increase to high and beat for 3 minutes.
Add orange extract and beat again for another minute. If you find the buttercream is too stiff, you may add milk or heavy cream 1 tablespoon at a time until the mixture is spreading consistency.
Fill the cake layers
Transfer 1/2 cup of the buttercream to a piping bag and pipe a circle of frosting around the outer edge of two cake layers. Fill the cakes with the orange filling. Stack the cake layers and cover the entire cake with a crumb coat of buttercream. Transfer the cake to the refrigerator and chill until the frosting is firm.
Cover the cakes with fondant
Cover a work surface lightly with vegetable shortening. Cover with confectioners’ sugar instead if working in humid conditions. Knead the fondant well before using. Using a smooth rolling pin, roll 3/4 of the fondant in a circle twice the size of the cake (to 1/4" thinness).
Drape fondant over the cake and gently fit and smooth it over the edges. Trim the fondant with a small paring knife or pizza cutter (recommended!). Place the cake on a cake stand or serving tray.
Make the Unikko flower pattern
Print the Marimekko template (see link in blog post) and cut out the flowers with scissors. Cut out the round flower centers and discard them. Place a little clear food color in a small dish and add red gel food color until a paint consistency is formed. Hold a flower template against the fondant and trace around it with a paint-loaded paintbrush. Take care not to smear the paint as you remove the template from the cake’s surface. Repeat until the sides of the cake are covered in flower outlines. You may choose to print additional flower templates if the ones you are using get too saturated with food color paint.
Fill in the outlines with red food color paint. Tint a small piece of fondant bright orange using the orange gel food color. Roll the fondant flat and cut out round pieces using a small fondant cutter or bottle cap. Squeeze the fondant so that the shapes are irregular. Paint a small black oval in the centers of the orange rounds using the black food color (dilute in a small amount of orange extract as before).
Attach the flower centers with a dot of corn syrup. Allow the cake to stand until dry at room temperature before serving.
Store leftovers covered in the refrigerator. Bring to room temperature before serving.