This one is not a slow cooker recipe. It is a bechamel made in a saucepan, folded through pasta and tuna, and baked at 375 degrees Fahrenheit until the top is golden — which is the only way to get a cheese crust.
Two ingredients carry the gluten-free label and both matter: certified gluten-free short pasta and certified gluten-free all-purpose flour for the roux.
Why This Recipe Works
- A butter-and-flour roux thickens the milk into a sauce that coats rather than pools, gluten-free flour included.
- Undercooking the pasta by two minutes stops it going soft during the bake.
- Cheddar split between the sauce and the top gives both a creamy interior and a golden crust.
- Dijon and garlic powder cut through the dairy so the bake does not taste flat.
Ingredient Notes
- Gluten-free short pasta
- Twelve ounces, certified, cooked two minutes short of the packet time.
- Gluten-free all-purpose flour
- Two tablespoons, certified. It makes the roux exactly as wheat flour would.
- Tuna in water
- Two 5-ounce cans, drained and flaked. It should stay visibly flaked through the pasta rather than dispersing.
How to Make It
Oven on, pasta short
Heat the oven to 375 degrees Fahrenheit. Cook the gluten-free pasta 2 minutes less than package directions; drain.
Make the sauce
Melt the butter in a saucepan, whisk in the gluten-free flour for 1 minute, then gradually whisk in the milk. Cook until lightly thickened. Stir in Dijon, garlic powder, salt, pepper, 1 cup cheddar and the Parmesan.
Fold and transfer
Fold the pasta and flaked tuna into the sauce and transfer to a baking dish. Top with the remaining 1/2 cup cheddar.
Bake to 165F
Bake 20 to 25 minutes, until bubbling, golden on top, and the center reaches 165 degrees Fahrenheit. Finish with parsley.
Saucepan, Then Oven
Forty-five minutes end to end, in three stages. The sauce is finished on the hob before the dish ever sees the oven.
Stage 1 of 3
The pasta, deliberately short
Steps 1–1 of 4
Oven to 375F. 12 oz of certified gluten-free short pasta cooked 2 minutes under the packet time and drained. It finishes cooking in the bake, and gluten-free pasta given its full time on the hob will be soft by the end.
- Oven on, pasta shortHeat the oven to 375 degrees Fahrenheit. Cook the gluten-free pasta 2 minutes less than package directions; drain.
Stage 2 of 3
The bechamel
Steps 2–2 of 4
2 tbsp butter, 2 tbsp certified gluten-free flour whisked in for a minute, then 2 1/2 cups of milk added gradually and cooked until lightly thickened. Off the direct heat it takes Dijon, garlic powder, salt, pepper, 1 cup of the cheddar and all the Parmesan.
- Make the sauceMelt the butter in a saucepan, whisk in the gluten-free flour for 1 minute, then gradually whisk in the milk. Cook until lightly thickened. Stir in Dijon, garlic powder, salt, pepper, 1 cup cheddar and the Parmesan.
Stage 3 of 3
Assembly and bake
Steps 3–4 of 4
Pasta and two drained cans of flaked tuna folded through the sauce, into a baking dish, the remaining 1/2 cup of cheddar over the top. 20 to 25 minutes at 375F until bubbling, golden and 165F in the centre. Parsley last.
- Fold and transferFold the pasta and flaked tuna into the sauce and transfer to a baking dish. Top with the remaining 1/2 cup cheddar.
- Bake to 165FBake 20 to 25 minutes, until bubbling, golden on top, and the center reaches 165 degrees Fahrenheit. Finish with parsley.
Success Tips
- Add the milk gradually and keep whisking, or the gluten-free roux will go lumpy.
- Fold the tuna in rather than stirring hard, so the flakes stay whole and visible.
- Check the centre temperature as well as the colour — golden on top can happen before the middle is at 165F.
Serving Ideas
Six servings from the baking dish, with the golden cheese crust intact and parsley over the top.
Frequently Asked Questions
Can I make this in a slow cooker?
No. It is an oven bake at 375 degrees Fahrenheit, which is what produces the golden crust.
Does the flour have to be gluten-free?
Yes. Both the flour for the roux and the pasta must be certified gluten-free.
How do I know when it is done?
Bubbling and golden, with the centre at 165 degrees Fahrenheit, at 20 to 25 minutes.
