Keto Zucchini Cannelloni (Low Carb, Gluten Free) - Sugar-Free Mom

Ingredients

• 2.5 cups my low carb Marinara Sauce (divided or Rao's brand)
• 1 tsp olive oil
• 1 ounce onion (finely chopped)
• 2 pounds ground beef
• 1 clove garlic (minced)
• 1/4 tsp salt
• 1 tbsp butter
• 1 cup heavy whipping cream
• 1/2 cup shredded mozzarella cheese
• 6 ounces cream cheese
• 1/4 cup grated Parmesan cheese
• 3 tbsp water
• 2 medium zucchini (about 14 ounces , sliced lengthwise)
• 2 ounces shredded mozzarella