Heat 2 tablespoons oil from sun-dried tomatoes in a large skillet over medium heat until shimmering. Add chopped onion, ½ cup sun-dried tomatoes and ½ teaspoon salt; cook, stirring often, until softened, 5 to 6 minutes.
Stir in chopped garlic, 1 tablespoon tomato paste, 1½ teaspoons Italian seasoning and ¼ teaspoon crushed red pepper; cook, stirring constantly, until fragrant and deep red in color, 1 to 2 minutes.
Stir in rinsed lentils and 3 cups broth; bring to a boil over medium-high heat. Cover and reduce heat to maintain a lively simmer; cook, stirring occasionally, for 10 minutes. Stir in 3 cups kale; continue gently simmering, covered and stirring occasionally, until the lentils are tender, about 5 more minutes.
Stir in ½ cup cream and 2 tablespoons basil; cook, uncovered and stirring occasionally, until the sauce is slightly thickened, about 2 minutes.
Remove from heat. Gradually stir in ¼ cup Parmesan, stirring until melted, about 1 minute.
Garnish with additional basil, if desired. Serve with toasted baguette.
