Preheat your oven to 350°F (175°C) and grease a 9-inch cake pan. Line the bottom with parchment paper.

In a large bowl, combine ricotta cheese and sugar. Use a hand mixer to beat until smooth and creamy, about 2-3 minutes. Add eggs one at a time, fully incorporate each before adding the next.

Stir in melted butter, lemon zest, lemon juice, and vanilla extract. Mix until evenly combined.

In a separate bowl, whisk together flour, baking powder, and salt. Gradually add to wet ingredients, folding gently until just combined.

Gently fold in chopped pistachios with a spatula, being careful not to overmix.

Pour the cake batter into the prepared pan and smooth the top. Bake for 30-35 minutes, until golden brown and a toothpick comes out clean.

After baking, cool in the pan for 10 minutes, then transfer to a wire rack to cool completely. Dust with powdered sugar and sprinkle with extra pistachios before serving.