Preheat oven to 375°F / 190°C / Gas Mark 5.
If desired, place berries in the freezer to firm up while you are making the muffin batter. *This helps to firm them up just slightly to prevent breaking while folding them into batter. They will not be fully frozen.
Line a muffin tin with 9 paper liners.
In a medium mixing bowl, whisk together melted butter, sugar, yogurt, eggs, almond and vanilla extracts. Set aside.
In a separate medium bowl, combine flour, salt, baking powder,and baking soda.
Pour wet ingredients into flour mixture and fold with a rubber spatula to combine.
Drop 2 tablespoons of batter into the bottom of each muffin liner.
Gently fold the berries into the remaining batter and fill muffin cups 2/3 full.
Generously top with the crumb topping, bake for 25 – 30 minutes, rotating the pan halfway through to ensure even baking. Test muffins with a wooden skewer, and when only a few moist crumbs are attached, remove from oven.(Check with a tester around 22 minutes, especially if your oven runs hot) Cool muffins in the muffin pan for 5 minutes before removing from pan, then place on cooling rack to cool completely.