WARNING!!!! I AM A FOODIE AND WILL PROVIDE MORE INFORMATION THAN YOU PROBABLY WANT....
In my 7 trips to Spain, I have had the most consistently delicious food (both in and out of restaurants) of anywhere I have travelled in the world. That said, having "comfort food" like your cajun seasoning might combat homesickness. For me, if I want everything to be (or taste) just like home, why travel?
As far as restaurants go, some have complained about the pilgrim's menus on occasion. In Spain (as elsewhere), you get what you pay for. I doubt that any of us would expect gourmet fare when being charged $10 for a three course meal in the U.S. or 10 Euros in Paris. Doing the Camino "on the cheap" and eating multi-course, delicious restaurant meals may not go together. The Pilgrims menus tend to be filling but not always (but sometimes) delicious. That said, northern Spain (especially the Basque ares) has one of the highest concentrations of "great" restaurants, including more Michelin stars per capita than anywhere in the world. So.... if you want great food, it is to be found along the Camino. But not for 7Euro.
For a real taste of Spain, maybe the best value is to get whatever is local/fresh in the market supplemented by the local tapas from the local bars.
Here are a few local products to look for in the MARKETS in the areas with which I am most familiar:
• In and around La Rioja: Pera de Rincón de Soto (large green pears); Claudia Reina Verde plums; Almonds & walnuts under the Nuez de Pedroso brand; Cauliflower; Red Peppers; Mushrooms (La Rioja produces 10% of all mushrooms sold globally!); white asparagus; Camerano cheese; La Rioja wine!!!!
• In Galicia: Pimientos de Padron (very small MOSTLY mild peppers; if they are in season you are blessed!); chestnuts; tetilla cheese; potatoes; grelos (turnip greens); the best, freshest, most diverse shellfish in Europe (if you are cooking in the evening); Galician bread (an amazing rye, cornmeal and whole wheat bread that are baked in HUGE loaves; ask for what you want by weight and they will slice it off the loaf for you); empanadas (giant seafood "pies" that are sold by the slice and make for a great meal while walking); local wines from Ribera Sacra (a Mencia-based red from the area just southwest of Sarria) and Albariño (white from the coastal area of Galicia).
• In markets everywhere: Jamon Serrano (ranging from the basic to the Iberico variety from free-range pigs that eat only the acorns that fall naturally from the oak trees of Extremedura and widely considered to be the best ham in the world); chorizo (unlike the Mexican version, this is a garlicky dried sausage more like a salami); many other things I am forgetting.
In BARS along the route:
• The local tapas, whatever they are... I love, love, love the little tastes of Spanish regions from the little skewers of pickled peppers, olives and anchovies in the Basque areas (Pamplona to Logroño+), to the pulpo (octopus) and tuna empanadas in Galicia, and everything in between.
• Tortilla Española – This delicious egg and potato pie (think fritata) is perhaps a perfect camino food. Even think about getting a slice in the evening to power your morning walk before breakfast is available. A great balance of carbs for energy and protein for longevity. Plus yummy.
• Good espresso (café solo) at every single bar in Spain. Heaven.
I won't really go into restaurants here. You might want to look into regional specialties such as Bacalao (salt cod) in Basque areas, roast suckling pig in Burgos,Caldo Gallego and shellfish in Galicia, etc. Suffice it to say, you cannot go wrong with these general rules of travel eating: 1) If the restaurant is filled with locals (especially families), eat there! 2) Ask the server if there is a house/regional specialty. 3) Be adventurous and try new things. 4) In bars, just point at the tapas that you want if you don't know what it is called.
Oh my.... I have gone on and on.... But you were warned. ¡Buen Camino y buen provecho!