Mini Coffee Pecan Layer Cakes

Name: Mini Coffee Pecan Layer Cakes
Prep time: 55 min
Cook time: 55 min
Total time: 55 min
Yield: 12 pieces
Ingredients: 4 Tbsp instant coffee granules; 4 Tbsp water; 100 g pecan nuts; 250 g unsalted butter; 275 g golden caster sugar; 300 g self-raising flour; 5 medium eggs; 2 tsp baking powder; 1 Tbsp natural vanilla extract; 250 g unsalted butter; 500 g icing sugar; 1 ½ Tbsp milk; 2 tsp natural vanilla extract; 12 pecan nut halves