01 - Preheat the oven to 350°F. Line a 12-cup standard muffin tin with paper liners or lightly grease each well with butter or oil.
02 - In a large mixing bowl, whisk together the ricotta cheese, whole milk, vegetable oil, eggs, vanilla extract, lemon zest, and lemon juice until the mixture is smooth and well blended.
03 - In a separate medium bowl, whisk together the all-purpose flour, granulated sugar, baking powder, baking soda, and salt until evenly distributed.
04 - Add the dry ingredient mixture to the wet ingredients. Using a spatula, fold gently until just combined — stop as soon as no dry streaks remain. Do not overmix, as this will produce tough muffins.
05 - Gently fold the raspberries into the batter with a few light strokes, taking care not to crush the berries and tint the entire batter pink.
06 - Divide the batter evenly among the 12 prepared muffin cups, filling each about three-quarters full. If desired, sprinkle the tops generously with coarse sparkling sugar for a crunchy, golden finish.
07 - Bake on the center rack for 20 to 24 minutes, rotating the pan halfway through, until the tops are golden and a wooden toothpick inserted into the center of a muffin comes out clean.
08 - Let the muffins rest in the pan for 5 minutes, then carefully transfer them to a wire cooling rack. Allow to cool completely before storing, or serve warm.