Place olive oil and butter in a medium saucepan and heat over medium heat. Add onion and cook stirring frequently for 3 to 4 minutes. Stir in garlic and continue cooking for 1 to 2 more minutes.
Sprinkle flour on top of wilted onions and continuously stir for about 10 minutes. Mixture should be a golden-brown color at the end of this time.
Slowly stir in the chicken broth using a whisk to incorporate the broth. When the mixture begins to simmer, stir in the cream and then return to a simmer.
Remove from heat and add Parmesan, chicken bouillon cubes, lemon juice, and sugar. Stir well.
Add sour cream, spinach, artichoke bottoms, Monterey Jack cheese, cayenne pepper, and Tabasco sauce. Stir until cheese has melted.
Serve warm with tortilla chips.