Peel and dice russet potatoes into approximately ½-inch cubes. Fill a large pot with water, add a pinch of salt, and bring it to a rolling boil over high heat. Once boiling, carefully add the diced potatoes and cook for about 12-15 minutes, until fork-tender. Drain and set aside.

Return the pot to heat and add frozen peas to the boiling water. Cook for an additional 3-5 minutes, until peas are tender and bright green. Drain and combine with potatoes, setting aside.

In a separate saucepan, melt butter over medium heat. Add finely diced onion and sauté for about 5-7 minutes or until translucent.

Pour in heavy cream, stir to combine, and bring the mixture to a gentle simmer for about 3-5 minutes, stirring continuously.

Remove from heat and fold in the boiled potatoes and peas. Season with dill, salt, and pepper to taste, folding until evenly distributed.

Transfer to a serving bowl and serve immediately alongside your favorite roasted meats.