Melt butter in a large heavy-duty bottom stockpot or Dutch oven over medium heat.
Add diced bacon and cook until fat renders and bacon begins to brown, about 3-4 minutes.
Add diced onion and minced garlic; cook until vegetables soften, about 5 minutes, stirring occasionally.
Add diced potatoes and chicken broth; increase heat to medium-high and bring to a simmer.
Reduce heat to medium and simmer for 8-10 minutes until potatoes are tender.
Add diced zucchini, corn kernels, heavy cream, salt, and pepper; simmer for another 8-12 minutes until all vegetables are tender.
Remove half of the chowder and place into a separate bowl.
Use an immersion blender to puree the remaining chowder until smooth.
Stir the pureed chowder back into the pot with the reserved half.
Adjust salt and pepper to taste.
Serve hot, garnished with chopped parsley, jalapeno, and a sprinkle of cayenne pepper if desired.