Pre-heat the oven to 200C (180C fan) / 400F. Line a muffin tin with papers.
Toss the raspberries in 1-2 tablespoons of the flour until they are lightly coated all over. Set 12 raspberries side (we’ll push them into the muffins at the end).
In a small bowl, stir the streusel ingredients together until they start to look shiny and coated in oil. Set to one side.
Place the milk, juice, oil, vanilla extract and sugar in a large mixing bowl and whisk with a fork until fully combined.
In a separate bowl, add the flour, baking powder, bicarbonate of soda and salt. Stir through to combine. Sift the dry ingredients into the wet ingredient bowl and gently stir until just combined. Fold in the raspberries, being careful not to break them up.
Gently scoop the batter into the muffin cups until they are ⅔-¾ full. Distribute the remaining 12 raspberries across the muffins, pushing them into the top of the batter. Sprinkle the streusel on top.
Bake in the oven for 25-30 minutes, or until a toothpick inserted through the middle is clean of batter. Leave to rest for a few minutes than transfer to a wire rack until completely cooled.
These muffins will keep for up to 3 days stored in an airtight container in the fridge or for up to 3 months in the freezer. To freeze them, place in a single layer in a freezer bag, squeeze out all the air and zip/ tie securely (this will help prevent freezer burn).