Make the strawberry puree. Add chopped strawberries, lemon juice, and optional sugar to a small saucepan. Cook over medium heat, stirring and mashing, until the berries break down and the mixture thickens, 8–10 minutes. You should have about 1/2 to 2/3 cup. Let it cool, then blend or mash until smooth. Reserve 1/3 cup for the batter and the rest for the glaze.

Prep the pan and oven. Heat oven to 350°F (175°C). Lightly grease a 6-cavity or 12-cavity donut pan. If using silicone, place it on a baking sheet for stability.

Mix dry ingredients. In a medium bowl, whisk flour, baking powder, baking soda, and salt. Set aside.

Mix wet ingredients. In a large bowl, whisk granulated sugar, brown sugar, and oil until sandy and combined. Add eggs one at a time, whisking until smooth. Stir in vanilla, yogurt, and the 1/3 cup reduced strawberry puree until evenly pink.

Combine batter. Add dry ingredients to wet and whisk gently until just combined. Fold in the finely diced strawberries. Do not overmix.

Fill the pan. Spoon batter into a piping bag or a zip-top bag with a corner snipped. Pipe into the donut wells, filling each about 3/4 full. Smooth tops if needed.

Bake. Bake 10–12 minutes for standard-size donuts, 8–10 for mini. Donuts are done when springy to the touch and a toothpick comes out clean or with a few moist crumbs.

Cool. Let donuts rest in the pan for 5 minutes, then transfer to a wire rack to cool completely. This helps them set and prevents sticking.

Make the glaze. In a bowl, whisk powdered sugar, a pinch of salt, and 2 tablespoons reduced strawberry puree. Add milk 1/2 teaspoon at a time until the glaze is smooth and thick but pourable. For a deeper color and flavor, add more puree and reduce the milk.

Glaze the donuts. Dip the tops of cooled donuts into the glaze, let excess drip, and set back on the rack. For a thicker coating, dip twice, letting the first layer set for 5 minutes. Optionally sprinkle with freeze-dried strawberry crumbs for extra color.