Hi! Does anyone have a good banana flavored filling for cake? I have a client that wants fresh banana for 2 of her 4 layer birthday cake. Since they're also ordering a huge amount of other desserts, I'd have to fill this cake 2 days before. so obvi fresh banana are out! Any and all ideas are much appreciated! Thanks!

Why don't you try a banana jam? Fresh bananas are not only impractical, but they are also risky. They get oxidized very quickly, and any mistake in the way you handle them, and the risk of food poisoning is high. 

Two nice options here, hope it helps!

Banana Jam - The Salted Pepper

Banana Jam Recipe : Make your own Banana Jam! - Mom Foodie

Can you carmelize bananas and put on top or inside a banana flavoured buttercream or pastry cream?

A banana pastry cream filling   4 large egg yolks ( no whites used). 3/4 cup sugar,1/4 tsp salt, 4 TBS cornstarch, 1 tsp vanilla, 1 tsp banana extract,  2 cups whole milk. 

   1.  In medium bowl whisk egg yolks and set aside.  In medium saucepan combing sugar, cornstarch and salt.  Blend together.   Gradually stir in 2 cups of milk.  Cook over medium heat, stirring constantly to dissolve the sugar.

2.  Bring mix to simmer.  Remove it from heat.  Spoon 1/4 to 1/2 cup of the hot sugar mixture into the bowl with egg yolks--stir constantly to temper the egg yolks.(  you don't want scrambled eggs)/

3.  Pour egg mixture into the saucepan , whisking constantly as it simmers( really important) until mixture thickens,  about 3 to 4 minutes.  When thickened remove from heat and add vanilla and banana extract... Filling will thicken as it cools.

4.  Pour into a heat proof bowl to cool.  Cover with plastic film wrap on top of filling so you won't get that skin.  Refrigerate until cold before using.

use a good quality banana extract for good flavour.

Pastry cream is risky as well, dairy and eggs get spoiled in the blink of an eye! If the cake is going to be at room temperature for more than an hour, and to be in the safe side, I will highly recommend that fillings must be fat and sugar based... My humble contribution...

What an interesting idea banana jam..........never heard of it and that recipe sounds great and easy to make!!

Well, kakeladi, next time do not pass those overripe bananas looking at you in the grocery store!