Berry Streusel Muffins

• 12 muffin tin
• 1 egg
• 3/4 blackberries (fresh)
• 220 gr golden brown sugar
• 220 gr unbleached all-purpose flour
• 170 gr raspberries (fresh)
• 120 ml milk
• 100 gr paper baking combine flour
• 65 gr pecans (chopped toasted)
• 65 gr butter (unsalted)