Clean the squid by removing the head, tentacles, inner guts, and cartilage. If desired, remove the thin film from the squid. Rinse them inside and out with cold water.
Thoroughly pat dry with paper towels. Score the squid, as this helps with cooking and a better presentation. Season with salt and pepper.
In a medium bowl, mix olive oil, lemon juice, garlic, ginger, soy sauce, and chili sauce. (Optional step: Heat remaining marinade in a small skillet over medium-high. Stir fry for about a minute, and adjust seasonings to taste. You may need to add some water to prevent it from burning.
Brush the marinade over the squid and let them marinate in the refrigerator for at least 30 minutes (or up to 2 hours). Reserve the rest for brushing the squid as they cook.
Preheat your gas or charcoal grill to medium-high heat (around 375-400°F/190-205℃).
Place them on the hot grill. Cook for 1-3 minutes per side or until the flesh becomes opaque and slightly charred, basting occasionally. Do not over-grill, as squid can get tough. Grill times will vary based on the squid's size.
Remove the squid from the grill and cut them into rings or leave them whole, depending on your preference.
Garnish with green onion.
Serve hot with extra sauce, rice, salad, or grilled vegetables.