1. Preheat the oven to 375°F / 190°C.

2. In a large mixing bowl, combine the ground chicken, salt, black pepper, and half a cup (120 ml) of the heavy cream. Mix until just combined.

3. Add the egg yolks and stir until smooth.

4. Heat the olive oil in a large skillet over medium heat. Add the butter and let it melt.

5. Use a spoon to drop small balls of the chicken mixture into the skillet, spacing them about 1 1/2 inches / 4 cm apart. Be careful not to overcrowd the pan.

6. Cook the chicken balls for 3 to 4 minutes on each side, until golden brown and cooked through to a safe internal temperature of 165°F / 74°C.

7. While the chicken cooks, make the lingonberry sauce by heating the remaining half cup (120 ml) of heavy cream in a small saucepan over low heat.

8. Stir in the lingonberries and let the sauce simmer for 5 to 7 minutes, until slightly thickened.

9. Serve the chicken balls with the lingonberry sauce, mashed potatoes, and steamed green peas. Enjoy your comforting meal!