High-Protein Spinach & Chicken Casserole for January Dinners

There’s something quietly heroic about a January casserole. It has to fight off the last of the holiday sparkle, the grey drizzle outside, and the “I should probably eat better” whisper that follows us into the new year. This high-protein spinach and chicken casserole was born on one of those slate-cold evenings when my kids were circling the kitchen like hungry sharks, I was determined to hit my macro goals, and the only thing in the crisper drawer was a fading bag of spinach and a half-block of feta left over from New Year’s Eve. One hour later the house smelled like garlic and lemon peel, we were all sitting at the table in thick socks, and even my pickiest eater asked for seconds. I wrote the recipe on the back of an electric bill, and we’ve made it every January since—because it tastes like comfort, but behaves like a personal trainer.

Ingredient Breakdown

I tested this casserole with everything from leftover holiday turkey to canned salmon, and the version that keeps us coming back starts with boneless skinless chicken thighs. Thighs stay juicy even if you overbake by five minutes (let’s be honest, we’ve all done it). Greek yogurt does triple duty: tenderizer, tangy contrast, and protein boost. Frozen chopped spinach is my January MVP—already washed, already chopped, and you can squeeze it dry with a clean tea towel while the oven preheats. Cottage cheese melts into creamy pockets that mimic ricotta without the price tag. A modest shower of feta on top gives those crave-worthy salty edges. Finally, a lemony dill panko crunch adds texture so every bite feels like a treat, not penance.

Full Ingredient List (Serves 6)

• 1 ¼ lb (560 g) boneless skinless chicken thighs, ½-inch dice high-protein base
• 1 cup plain 2 % Greek yogurt tenderizer + protein
• 2 tsp garlic powder, 1 tsp onion powder, 1 tsp dried oregano speedy flavor trio
• 10 oz (280 g) frozen chopped spinach, thawed & squeezed dry greens without fuss
• 1 cup low-fat cottage cheese creaminess & calcium
• 2 large eggs structure so squares hold
• ½ cup crumbled feta + ¼ cup grated Parmesan umami bomb
• Zest of 1 lemon + 2 Tbsp juice brightness
• ¼ cup panko (or almond meal for GF) crispy lid
• 2 Tbsp fresh dill, chopped winter herb lift
• 1 Tbsp olive oil, salt & pepper pantry staples

Step-by-Step Instructions

1. Marinate the chicken (15 min–12 hr): In a big bowl, combine diced chicken, Greek yogurt, garlic powder, onion powder, oregano, ½ tsp salt, ½ tsp pepper, and 1 tsp lemon juice. Stir until every cube is coated. Cover and refrigerate at least 15 minutes—overnight is gold.
2. Heat oven & prep pan: Preheat to 400 °F (204 °C). Lightly oil a 2-quart (8-inch square) casserole or six mini ramekins for cute individual bakes.
3. Make the spinach filling: In the now-empty yogurt bowl (save a dish!) whisk eggs, cottage cheese, spinach, lemon zest, 1 Tbsp lemon juice, and half the feta. Taste and add salt; remember feta is salty.
4. Layer: Spread half the spinach mixture on the bottom. Top with marinated chicken (scrape in all that yogurt). Spoon remaining spinach mix over chicken and sprinkle with remaining feta and Parmesan.
5. Add crunch lid: Toss panko with olive oil, dill, pinch salt, and pepper until evenly moistened. Scatter over casserole.
6. Bake: 25–30 minutes (18–20 for ramekins) until the top is golden and the center registers 165 °F (74 °C) on an instant-read thermometer. Broil 1 minute if you like extra bronzing.
7. Rest & serve: Let stand 5 minutes so the proteins set and you get tidy squares. Finish with extra dill and a squeeze of lemon.

Expert Tips & Tricks

• Squeeze spinach like your life depends on it: A soggy casserole is a sad casserole. I twist mine in a flour-sack towel until zero water drips.
• Double-batch marinade: Double the yogurt-spice blend, freeze half the raw chicken in it, and next month you’ll have ready-marinated meat.
• Thermometer > guesswork: Chicken cubes hide in spinach; temp the center cube to dodge dry bites.
• Make it melty: Stir ½ cup shredded mozzarella into the spinach layer for the world’s most virtuous “spinach-artichoke” vibe.
• Crisp panko hack: Toast crumbs in a dry skillet for 2 minutes before mixing with oil; they’ll stay crunchy even after refrigeration.

Common Mistakes & Troubleshooting

Variations & Substitutions

• Low-dairy: Swap yogurt for coconut yogurt, cottage cheese for firm tofu blended with 1 Tbsp nutritional yeast, and omit feta or use vegan feta.
• Mediterranean twist: Add ½ cup sun-dried tomatoes and replace dill with 1 tsp dried oregano + ¼ tsp cinnamon.
• Broccoli cheddar vibe: Trade spinach for finely chopped broccoli florets and fold in ¾ cup sharp cheddar.
• Turkey leftover edition: Use diced cooked turkey; shorten bake to 15 min—just to heat through and melt top.
• Spicy kick: Stir 1 Tbsp harissa into yogurt marinade and swap feta for pepper-jack.

Storage & Freezing

Cool completely, then cut into six squares. Refrigerate in airtight glass up to 4 days. For longer storage, wrap each square in parchment, stack in a zip bag, and freeze up to 3 months. Reheat single portions in the microwave 90 seconds (add a splash of water and cover) or bake from frozen 25 min at 350 °F. The panko won’t be quite as crisp after freezing, but a 1-minute sizzle in a hot skillet restores crunch like magic.

FAQ

Here’s to a January that tastes like comfort, feels like resolve, and cleans up in under five minutes. Grab that forgotten bag of spinach, dice the chicken, and let the oven turn simple into spectacular—one protein-packed square at a time.

High-Protein Spinach & Chicken Casserole

Chicken

4.6 (112 reviews)

Prep

15 min

Print Recipe Pin Recipe

Cook

35 min

Total

50 min

6 servings

Easy

Ingredients

• 2 cups cooked chicken breast, shredded
• 10 oz baby spinach, chopped
• 1 cup low-fat cottage cheese
• 1 cup plain Greek yogurt
• 3 large eggs
• 1 cup part-skim mozzarella, shredded
• ½ cup Parmesan, grated
• 1 small onion, finely diced
• 2 cloves garlic, minced
• 1 tsp olive oil
• ½ tsp red-pepper flakes
• ½ tsp dried oregano
• Salt & black pepper to taste
• Non-stick cooking spray

Instructions

1. Preheat oven to 375 °F (190 °C). Lightly coat a 9×13-inch baking dish with non-stick spray.
2. Heat olive oil in a large skillet over medium heat. Sauté onion until translucent, about 3 min. Add garlic and red-pepper flakes; cook 30 sec.
3. Stir in chopped spinach, season with salt and pepper, and cook until wilted, 2–3 min. Remove from heat and cool slightly.
4. In a large bowl whisk together cottage cheese, Greek yogurt, eggs, oregano, and half the mozzarella until smooth.
5. Fold in shredded chicken and the cooled spinach mixture until evenly combined.
6. Spread mixture into prepared dish. Top with remaining mozzarella and Parmesan.
7. Bake 30–35 min until the casserole is set in the center and golden on top. Rest 5 min before slicing.

Recipe Notes

Make-ahead: assemble the night before, cover tightly, and refrigerate. Add 5–10 extra minutes to bake time if chilled. Leftovers reheat well for up to 4 days or freeze individual portions for up to 2 months.

Nutrition (per serving)

Calories: 285

Protein: 34 g

Carbs: 9 g

Fat: 11 g

Fiber: 2 g

Sugar: 4 g