Pre-heat the oven to 180°C / 160°C fan assisted /gas mark 4 / 350°F and prepare a 12 hole muffin tin with muffin liners.
Place the sugars, eggs, olive oil, milk, thyme and vanilla in a large bowl and beat together until smooth.
In a separate bowl whisk together the flours, baking powder and salt until thoroughly combined.
Add the flour mixture to the batter and beat together until smooth.
Stir in the chocolate chips and the blackcurrants until evenly dispersed.
Divide the batter into muffin cases, filling to just below the top.
Bake in the oven for about 20-25 minutes until risen and the blackcurrants are bursting out.
Remove the muffins from the tin straight away to cool on a wire rack.
Drizzle with extra melted white chocolate if you like.