In a large pot, sauté garlic and onion in butter over medium heat until fragrant.
Add vegetable broth, orzo, lemon zest, salt, pepper, and red pepper flakes. Bring to a simmer.
Add broccoli florets and cook until orzo is tender, stirring occasionally.
Stir in white wine, lemon juice, and Parmesan cheese until well combined.
In a separate pan, melt butter and toast panko breadcrumbs until golden brown.
Serve the orzo topped with toasted breadcrumbs and additional Parmesan cheese, if desired.
