Bring a large pot of water to a boil. Add perogies and cook stirring occasionally for 5 mins. Drain and set aside.
In a large sauté pan over medium heat, heat oil and sauté onions until soft translucent and slightly golden.
Add white wine and cook for 1-2 minutes. Add lemon juice and bring to a boil. Cook until reduced to half, 2 -3 minutes.
Add butter and capers and sauté for an additional 2-3 minutes until sauce is creamy and slightly thickened.
Add perogies and season with pepper. Sauté stirring until perogies are well coated with sauce. Serve warm.