In a large mixing bowl, mix the Butter and Sugar to form a dry paste. Add the vanilla extract.

Add the Eggs and mix well, making sure the eggs are totally absorbed.

Add the All-Purpose Flour and Baking Powder (If you have and know what Self Raising Flour is, you can use that instead).

Add the Lemon Zest and Blueberries. Mix the ingredients until all the berries are totally absorbed into your cake batter.

Prepare the cake tin by using some grease-proof paper to line the tin with butter or Margarine. This helps the cake slide out once the cooking cycle has been completed.

First place the inner pot inside the Instant Pot. Now add 2 cups of water to the inner pot. Then place a lower trivet with handles inside the main pot. Set the Instant Pot aside.

Now pour your cake batter into the greased 7-8 inches wide Cake Pan.

Cover the pan with foil or a paper towel. Place the pan inside the inner pot and on the trivet.

Add the cake pan to the Instant Pot. Close the lid on the Instant Pot and set the valve on SEALING.

Press the CAKE BUTTON and bake it for 40 minutes. If You Do Not Have a Cake Button, Press Pressure Cook and Set for the same time using the high-pressure button.

Once cooked follow a NPR natural pressure release.

Be careful when you take the cake pan out of the Instant Pot, as it will be VERY hot. Use some tongs or wooden spoons to lift the cake tin out of the Instant Pot, then use oven gloves to avoid being scolded. Let sit in the cake pan for 10 minutes.

Once the cake has cooled, you can then drizzle it with any icing of your choice.