Melt butter with canola oil in 10-inch skillet until sizzling; add garlic and onions.
Cook over medium heat, stirring occasionally, 4-5 minutes or until onions are translucent.
Add spinach, saute 2-3 minute or until spinach is wilted.
Whisk eggs and salt together in bowl.
Add eggs to vegetable mixture in pan; sprinkle with basil.
Cover; continue cooking 4-6 minutes or until center is almost set.
Sprinkle with cheese. Cover; remove from heat. Let stand 2-3 minutes or until cheese is melted.
Cut into wedges. Garnish with chopped tomatoes.