Place the 3 tea bags and milk in a small saucepan over medium heat and gently bring to a simmer. Place lid on the saucepan, remove the pan from heat and set aside for the tea to ‘brew’ until the milk is cool.
Preheat the oven to 180°C (350°F). Prepare the cupcake pan by placing the cupcake paper cases into the pan moulds.
In the bowl of a stand mixer fitted with the paddle attachment, beat the butter and sugar until light and fluffy; this takes about 3 minutes. Add the egg and vanilla extract and beat for a further two minutes. Fold in the flour, baking powder and salt and the Earl Grey tea leaves of the remaining Earl Grey teabags. Pour ¾ cup of milk into the mixture and stir until combined.
Pour mixture into cupcake cases until ⅔ full. Bake in the oven for 18-20 minutes or until a toothpick inserted into the centre comes out clean. Remove from the oven and let cool slightly before transferring to a wire rack.
Combine blackberries and lemon zest into a small saucepan with 100ml of water. Over low heat, bring to a simmer and cook until the blackberries are soft and broken up with a wooden spoon.
Place a sieve over a medium-sized bowl, remove the pan from the heat and push the blackberries through the sieve with a spoon. Discard the pips/pulp and set aside the strained blackberry juice.
Add sugar, butter, cornflour and lemon juice into a small saucepan over low heat and stir until the butter has melted and combined.
Add the eggs, whisk continuously but gently, then add the blackberry juice. On a medium to low heat, slowly bring the temperature of the mixture up until it starts to thicken and coats the back of a spoon. This takes 5-10 minutes. Be sure to scrape down the sides and the bottom of the pan so that the mixture heats up evenly.
Pour into a medium bowl and cover by placing cling film directly onto the curd so that a ‘skin’ doesn’t form. Set aside to chill.
Cream Cheese frosting
In the bowl of a stand mixer fitted with the paddle attachment, beat the butter and cream cheese for 3 minutes until well combined. Add vanilla extract and salt and beat till mixed in. With your mixer on low, gradually add your icing sugar into the bowl until fully combined.
Once the cupcakes have cooled completely, with a teaspoon, scoop out a hole in the cupcake centre. Spoon blackberry curd into the hole until level with the top of the cupcake. (You can save the scooped out sponge to nibble on now or later!).
Using a piping bag, or smoothing with an offset spatula, decorate each cupcake with the cream cheese frosting.
Optional: Top the cupcakes with an individual blackberry, mint leaf and a dollop of curd. Pour yourself a cup of tea and take a huge bite of that cupcake and enjoy!!