Slice and quarter your strawberries. Toss them with the salt and raw sugar and spread them on a parchment lined baking sheet. Bake for about 30 minutes, until jammy and starting to brown on the edges.
Increase oven temperature to 375 degrees.
Butter and line an 8 inch round baking dish (I used a cake pan; you could substitute a larger dish for thinner bars).
In a stand mixer with the paddle attachment, beat together the flour, oats, butter, sugar, baking powder and salt (you could also do this by hand). Once the dough is crumbly and well-mixed, press 2 cups of the dough into the pan. Make sure it is all pressed down.
Add the roasted strawberries on top with a couple extra tablespoons of raw sugar (depending on how sweet you like it). Mash the strawberries into a jammy layer with the back of a spoon.
Add the remaining dough on top and press lightly.
Bake for 25 minutes, until the top begins to get golden brown. If you eat it warm, it will be a little looser in texture.