• Preheat outdoor grill or stovetop grill pan.
• Spray tenderloin on all sides with olive oil spray (or brush on a thin layer of oil).
• Grill on all sides until well browned, about 7 - 8 minutes. Transfer to a baking sheet.
• Preheat the oven to 400 degrees Fahrenheit.
• In a small bowl combine garlic, olive oil and rosemary. Rub over tenderloin and season generously with salt and pepper.
• Bake until desired doneness: 10 - 15 minutes for rare (120 degrees), 15-20 minutes for medium (130 degrees), or 25 minutes for well done (140 degrees). Let rest for 20 minutes before carving.
• While beef is roasting, prepare the sauce.

Sweet Corn sauce:

• In a small saucepan, cook onion in butter until translucent but not browned, about 5 - 8 minutes.
• Add corn, broth, and water; bring to a boil for 5 minutes.
• Using an immersion blender (or a conventional blender), process the corn mixture until smooth.
•  Strain through a fine mesh strainer; discard the solids. Season corn mixture with salt and pepper and stir in chives.
• Carve roast to desired thickness and arrange on a serving platter. Serve sauce hot with carved tenderloin.