These are what berry muffin dreams are made of. A super soft, delicate crumb, a hefty burst of fresh berry flavor and a crunchy, leave-you-wanting-more subtle lemon scented topping.
Preheat the oven to 400f/200C and spray a 12-cup muffin tin with baking spray or line with muffin papers.
Start with the topping first. Add all the topping ingredients to a medium-sized bowl and combine with a fork or your fingers until crumbly. Set in the refrigerator.
Take a tablespoon from the measured flour and sprinkle it over the berries in a small bowl. Toss to coat. Then in a large bowl, add the remaining flour, sugar, baking powder and salt. Stir to combine.
In a liquid measuring cup or medium bowl, whisk together the buttermilk, oil, eggs and vanilla. Then slowly whisk in the melted butter.
Add the buttermilk mixture to the bowl with the dry ingredients then use a spatula to gently combine until almost incorporated . Do not over mix. Then fold in the berries until combined and no flour streaks remain.
Divide the batter among the muffin cups using a large cookie scoop or spoon. (I fill them all the way to the top for the muffins pictured.) Place 1 teaspoon of the raspberry jam on the top of each muffin and slightly swirl with a toothpick. Spinkle the crumb topping evenly on the muffins. Bake for 10 minutes then turn the heat down to 350F/177C and continue to bake until the muffins are light golden brown at the edges and a toothpick or thin knife inserted into the center of a muffin comes out clean, about 20-25 minutes more. (if you make the muffins smaller, they will bake in less time.) Immediately remove the muffin tin to a wire rack and cool. Serve immediately or at room temperature.