Make the jelly/jello up according to instructions on the packet in advance, so it sets well before you use it. Set it in a large container so that the jelly is not too deep. Dice it into squares when ready to assemble the trifle.
Make the Low Carb Custard as per the recipe link in advance and allow to cool and thicken in the fridge.
Make the Simple Low Carb Sponge Cake as per instructions below in advance.
Whip the cream with the sweetener and vanilla extract just prior to assembling your trifle.
A Simple Low Carb Sponge Cake Method
Preheat the oven to 175 C/350 F Fan Forced and prepare the baking pan with oil/butter and baking paper.
Beat the egg whites until light and fluffy and set aside.
Beat the egg yolks with the sugar and vanilla extract
Whisk the dry ingredients to make sure the baking powder is well dispersed.
Pour the egg whites and the egg yolk mixture over the dry ingredients and gently fold in, using minimal stirring but ensuring the batter is well combined.
Pour the batter into the prepared baking pan and smooth out the top.
Bake in the oven until for about 20-27 minutes or until the cake is cooked in the centre.
Allow the cake to cool slightly before inverting. Wrap in cling wrap and allow to cool until ready to assemble the trifle.
Just prior to assembling the trifle, cut the cake in half and with the crumb side up, sprinkle half the Sherry onto each side. Cut the cake into small 2.5 cm/ 1"cubes.
To Assemble the Trifle
Slice 6 large strawberries into thin slices (approximately 6 slices per strawberry) and stick a row of them around the bottom edge of the trifle bowl, facing outwards.
Lay half of the cake pieces on the bottom of the trifle bowl and then add another row of strawberry segments around the side of the bowl, just above the first row of strawberries.
Sprinkle 3/4 cup of berries on top of the cake and then top the berries with half of the cubed jelly. Pour half of the cold custard over the jelly (not warm or it will melt the jelly.)
Repeat the layers 1 more time starting with the other half of the cubed cake, then top with 3/4 cup of berries and finally add the remaining half of the jelly.
Finish off with a layer of the remaining custard. Smooth off the top. Top the custard with whipped cream, and decorate with remaining berries, chopped/slivered almonds, mint leaves etc.
Store in the fridge for a minimum of 4 hours before serving.
Notes
This will keep for 3 to four days in the fridge.Allow the custard to cool in the fridge to thicken and ensure it is cold. If you make the trifle in advance, you may wish to top it with cream and decorate it just before you serve it so the topping is fresh.