Method:
Pre-heat oven to 140 C, rack in the middle and grease 2 cake pans ( 12 cm ) with some butter then dust with flour and put a piece of parchment paper on the bottom to make it easier to get the cake out.
Pour boiling water over the dates in a small bowl and set aside to cool down for 10 minutes.
In a separate bowl whisk all dry ingredients and set aside.
In your electric mixer, beat eggs and sugar till pale in color, add oil beat a bit then add the yogurt, then dry ingredients and mix using a spatula till all well combined, add dates with the soaking water, mix well then add pecans.
Divide the batter between pans and bake for 30 minutes or until a toothpick comes out clean.
Allow the cakes to cool down completely on a wire rack.
Make the toffee buy mixing all ingredients in a sauce pan over a medium heat and let it simmer for 3-4 minutes ( or till its thick enough ) then take it off heat and allow to cool to room temperature.
Place egg whites and sugar in the bowl of an electric mixer, Whisk by hand to combine then place it over a saucepan filled with some boiling water to create a double boiler.
Keep stirring for some time till u can feel the mixture is hot when u try to dip your finger, take it off the pan and place it in the electric mixer, beat the mixture till the bowl turns back to normal temperature, now start adding the butter one tablespoon at a time, turn the mixer to medium speed till the cream becomes smooth.
Slice each cake to 3 layers, place the first layer on your cake stand, pour some warm sugar syrup if you the cake to be super moist, if not just skip it, scoop some buttercream and spread it evenly, add a thin layer of toffee then cover with another cake slice and repeat for the rest of cake slices then cover the whole cake with a thin layer of buttercream, so you can still see cake layers, top it with toffee and let it drop down the sides, decorate with some dates and pecan and let it cool down in the fridge for at least 5 hours before serving.