Cut the top inch off of each asparagus stalk. Bring a large pot of salted water to a boil over high heat. Have a large ice bath ready. Add asparagus tips and cook until bright green and tender, about 1 minute. Transfer to ice bath until chilled. Dry carefully and reserve. Add asparagus stalks to water and cook until bright green and tender, about 2 minutes. Transfer to ice bath to chill; then transfer chilled stalks to a blender.
Set aside 4 ramps. Heat 1 tablespoon olive oil in a large skillet over medium-high heat. Add remaining ramps and season with salt and pepper. Cook, stirring and tossing frequently, until tender and lightly browned. Transfer to blender jar. Add broth and yogurt to blender. Blend on high speed until completely smooth; add more water as necessary until consistency is soupy.
While blender is running, slowly drizzle in 2 tablespoons olive oil. When combined, strain mixture through a fine mesh strainer.
Transfer to a medium saucepan and heat, stirring frequently. Season with sea salt and pepper, to taste. Add lemon juice, to taste.
Heat a drizzle of olive oil in the pan and sauté ramps and asparagus tips until lightly browned.
Divide the soup between two bowls, drizzle with yogurt and top with sautéed ramps and asparagus. Serve.