Gather all the ingredients and preheat the oven to 180ºC/356ºF.
Sift all the dry ingredients into a mixing bowl.
Using the stand mixer with the paddle attachment, cream the butter and sugar, on medium speed, until fluffy and very pale - about 5 minutes.
Meanwhile, whisk the eggs, lemon extract, yogurt and milk in a small bowl.
Scrape the bowl of a stand mixer and add the wet ingredients. Mix on medium speed until well incorporated.
With the mixer on low speed, add all the dry ingredients and mix until about 75% of the batter is mixed in. Turn off the mixer and scrape the batter clinging onto the paddle attachment.
Add the raspberries. Using a large spatula slowly mix by folding the batter and raspberries over - Note 1.
Using the ice cream scoop, divide the muffin batter evenly into the prepared muffin baking tray. Level the batter with a spatula.
Sprinkle the chopped pistachios over each muffin.
Bake for 25 minutes at 180ºC/356ºF - Note 2.
NOTES
Make sure not overmix and break many raspberries. Some will break but that's OK.
Muffins are cooked when the toothpick inserted in the middle of the dough part comes out clean.